Seattle Aquarium

  • By Patrick McRoberts and John Caldbick
  • Posted 11/05/2014
  • Essay 2203

Seattle's waterfront is a natural location for an aquarium, and proposals to build one go back many years, though it wasn't until a Forward Thrust bond issue was approved in 1968 that funds were allocated for a true municipal aquarium. After haggling over the location, a site at piers 59, 60, and 61 on the central waterfront was approved in 1973. The Seattle Aquarium opened on May 20, 1977. Over the years, despite management turnover and delays in new exhibits during the 1980s, the Seattle Aquarium provided a recreational and educational resource for millions of visitors. Starting in 2006, a $41 million renovation replaced the pilings under Pier 59 and rebuilt the pier's shed, which had been awarded historical-site status. New features were added, including a 20-foot-high, 120,000-gallon floor-to-ceiling fish tank near the aquarium's new entrance on Alaskan Way. In 2010, management was transferred from the city to the Seattle Aquarium Society, a nonprofit. In 2024 the Aquarium's newest expansion -- the Ocean Pavilion -- is scheduled to open. Integrated into the new Overlook Walk connecting the waterfront to Pike Place Market, the Ocean Pavilion will include a 350,000-gallon tank populated with sharks, rays, and other sea creatures from the Pacific Ocean. 

Municipal Aquarium for a Maritime City

Although the Seattle Aquarium had precursor institutions, such as the Seattle Frozen Fish Aquarium and the Seattle Marine Aquarium operated by Ted Griffin in the 1960s, the city's first true municipal aquarium was born with the passage of the Forward Thrust bond proposal in 1968. Forward Thrust was a package of a dozen separate bond measures, some countywide and others citywide. The King County parks and recreation bond included $3 million to build an aquarium. Seven of the 12 proposals passed on February 13, 1968, including the parks and recreation measure, which passed by about 65 percent. A proposal to build a stadium (later called the Kingdome) also passed, while a rapid-transit measure failed.

Following the vote, a controversy arose over where to build the aquarium. Pacific Science Center director and future Governor Dixy Lee Ray (1914-1994), along with Liem Tuai, chair of the city council's Parks and Public Grounds Committee, supported a site at Meadow Point north of Golden Gardens Park in Ballard. Environmentalists opposed the site, arguing that it would destroy one of the last natural Puget Sound beaches inside Seattle. Ray disputed this, calling it "sentimental emotionalism." She argued, "a properly designed aquarium at Meadow Point could restore the area to something like its natural state. Native dune grasses and shore plants could replace the scotch broom that grows there. Shore life could be restored in demonstration plots and pools. An aquarium at Golden Gardens would enhance the environment, not destroy it" ("Aquarium at Golden Garden OK'd").

The city council flipped back and forth on the issue, first passing a proposal to build the aquarium at the Ballard site on April 5, 1971. (This was the same week in which the council agreed to acquire central waterfront property, including piers 59, 60, and 61, the eventual site of the aquarium, for a waterfront park.) Then, after an initiative opposing the Ballard location was filed, the council passed a measure on December 17, 1971, prohibiting the location of the aquarium at that site. Other sites considered included Fort Lawton and several central waterfront locations. Lockheed shipyards even proposed building the aquarium on a ship so it could be moved from location to location. Finally, on July 3, 1972, the council proposed to build the aquarium at piers 60 and 61. Pier 59 was added to the site as a result of a proposal by parks superintendent Dave Towne, made on October 29, 1973. Towne argued that Pier 59 was the best place to build the aquarium because it wouldn't involve demolishing piers 60 and 61. (Piers 60 and 61 were later taken down to provide room for aquarium expansion.)

Grand Opening 

Advance reviews of the aquarium building were highly favorable, and shortly before it opened, the American Consulting Engineers Council awarded the aquarium's developers the Grand Conceptor Award for the highest achievement in engineering excellence in 1977. Then, on May 20, 1977, the Seattle Aquarium held its grand opening for excited crowds, nearly a decade after voters approved its initial financing. While the cost of the project had increased, the city had adjusted budgets to meet expenses. 

A total of 1,524 visitors toured the facility on opening day, when thousands of fingerling salmon were released into Elliott Bay with the hope that they would return to the aquarium fish ladder to spawn. Inside the aquarium, visitors walked along ramps viewing sponges, jellyfish, snails, clams, and crabs, most of them native to Puget Sound. The glassed-in Aquarium Dome allowed visitors to sit on benches and watch fish watching them. Sea otters performed tricks in return for horse clams, while an octopus clung to a pier. Many of the animals inhabited outside viewing areas in their natural habitats, enabling visitors to watch sandpipers hunting for food or ducks nesting in grass. Mayor Wes Uhlman said the aquarium "expresses the relationship we in Seattle have with the sea." Towne, the former city parks director, called the grand opening "the biggest new show in town." In the first four months of operation, attendance exceeded expectations, totaling 353,000 visitors.

In September 1979, seven 2-year-old coho salmon returned to the aquarium's fish ladder to spawn. These salmon had been released in May 1978 in the hope of establishing a continuing salmon run at the aquarium, making it possible for viewers to study the spawning, incubation, and release of young salmon. One chinook salmon from an earlier release also made it up the ladder. The year 1979 also saw the opening of the OmniRama, an Imax theater that was one of about a half dozen in the world. The theater showed extra-large film in a dome-like setting to give three-dimensional effects.

Trials and Errors

The early 1980s were a time of trial for the aquarium. Founding director Doug Kemper was forced out in June 1981 after disputes with the Seattle Parks and Recreation Department. Parks director Walter Hundley blamed "general management problems" for declining attendance. Kemper countered that the city was not giving enough support to new programs. He wanted to see the aquarium managed by a nonprofit organization, as was the trend with many similar institutions, and led the effort to found the Seattle Aquarium Society (SEAS) in 1981. After Kemper's departure, the city considered merging the aquarium and Woodland Park Zoo under a single director. Eventually, Mayor Charles Royer tabled that plan. Kemper's replacement, Ronald Glazier, left three-and-a-half years later under similar circumstances. At that point, attendance had been declining for four years. Glazier said the lack of major new exhibits was the reason. 

Still, the aquarium continued its mission as a recreational and educational resource. In 1982, it received an Edward H. Bean Award from the American Zoo and Aquarium Association for being the first to successfully breed a giant Pacific octopus in captivity. The aquarium also sponsored off-site tours and cruises to expose visitors to aquatic life in the wild.

On August 13, 1986, a $180,000 exhibit exploring the "State of the Sound" opened. The aquarium believed the exhibit, about the health of Puget Sound, was the first in the nation to focus on the local environment. Paid for with city, state, federal, regional, and private funds, the exhibit featured stations where visitors could take water samples and lower traps into the water to catch marine life that lurks beneath Seattle's piers. Visitors could check Puget Sound's temperature, salt content, and tide level. Using a white marker known as a secchi disc, they could determine the water's cloudiness, a factor that changes with storms and the tide.

Issues of funding and the aquarium's management structure were themes in the late 1980s and 1990s. In August 1986, Mayor Royer put forth an ambitious expansion plan for the aquarium as part of an overall waterfront improvement package. Eventually, the plan was split in two, with the other waterfront improvements going to a citywide vote and the aquarium rolled into a countywide bond measure. On June 10, 1988, the King County Council voted unanimously to put forward an $85.8 million proposal to buy open space, acquire trails, and expand the aquarium. The measure would have provided $25.4 million for the aquarium, but it received only 50.8 percent of the vote in the September 1988 primary, well short of the 60 percent needed. The waterfront improvement measure also lost. 

Into the New Century

On March 12, 1999, a crowd of school children bid farewell as Ursula, a 40-pound octopus, was released into Puget Sound to breed. Ursula set up housekeeping under the aquarium pier. Romance was in the water when a male octopus moved into a nearby den. Exhibits in 2000 included the Pacific Coral Reef; a giant Pacific octopus named the Shadow; the Sound to Mountains exhibit, which included river otters, an aquarium first; sea otters; Discovery Lab; and the Underwater Dome, in which visitors were surrounded by 400,000 gallons of water and myriad sea creatures. Off-site adventures included Eaglewatch 2000, Whalewatch 2000, scenic cruises, and kayak training and trips. The aquarium undertook Washington's first census survey of giant Pacific octopuses and rehabilitated two errant tropical sea turtles found off the Washington coast.

Financial problems continued. In February 2000 a bill that would have allowed Seattle residents to vote on a property-tax increase to pay for expansion of the aquarium (and the Woodland Park Zoo) died in the state legislature. This was followed a few months later by the resignation of the aquarium's director, Cindi Shiota, who left after 12 years in the post, saying that working 80-hour weeks had harmed her health. Bill Arntz, former chairman of the Seattle Board of Park Commissioners, was named acting director in July 2000.

During this unsettled period, the Seattle Aquarium Society and city officials continued to push for a new aquarium; preliminary architectural plans were developed, there was a tentative commitment of $21 million from the city council, and the society expressed hope that it could raise the needed remainder from private contributions. But debate took precedence over doing. Study followed study, delay followed delay, and little progress was made.

Meanwhile, the rehabilitated sea turtles were successfully returned to the wild, and a sea otter, Yaku, was born on April 19, 2000, the fifth such birth in the world's first successful captive-breeding program for the irresistibly cute aquatic mammals. The annual Salmon Homecoming Celebration was held in September 2000, and the aquarium's popular education programs for young people continued.

The facility, however, was now nearly 25 years old, showing its age and requiring ever-increasing expenditures for maintenance and repair. All parties agreed that something needed to be done, but there was little agreement about what that was, or even precisely where it should happen. The aquarium society had wanted to build a new facility at piers 62 and 63, but was opposed by groups seeking to preserve waterfront views and open space. This impasse was resolved in February 2001 when the society agreed with a citizens advisory committee that the aquarium would remain sited around piers 59, 60, and 61. Instead of a new aquarium at a different location, plans pivoted to an expanded and improved aquarium at its existing site. Still, contrasting visions remained at play. For example, the aquarium wanted to move the pier shed it occupied on Pier 59 a little nearer to Waterfront Park, but other groups were seeking historical-site recognition for the shed, which would likely prevent such a move. As with most complex plans, the devil remained in the details -- siting, funding, design -- and the lack of consensus remained a roadblock to meaningful progress. It would be years before real movement was made toward a new or greatly expanded aquarium.

The aquarium celebrated its 25th anniversary with fanfare in 2002 and gradually improved and upgraded its permanent and special exhibits. Educational and scientific programs also continued and expanded, steered by a dedicated staff aided by hundreds of volunteers. The Seattle Aquarium was a vibrant institution marooned in an inadequate space on a waterfront needing major repairs, but it remained an entertaining and informative destination for residents and tourists alike.

Waterfront at Risk

The one thing advocates of a new aquarium did not need was to become part of a larger debate, but the Nisqually earthquake in February 2001 made that inevitable. Damage caused by the earthquake revealed just how catastrophic a larger earthquake could be, possibly toppling the aging Alaskan Way Viaduct or causing the collapse of the seawall protecting the waterfront from the waters of Elliott Bay. Some of the seawall dated to 1916, but most of it had been completed in the 1930s. Built largely of old-growth trees and 250,000 cubic yards of dirt, it had helped Seattle to become a major seaport, but the chance it might fail was now an existential threat. There was not much sense in committing tens of millions of dollars to an aquarium until it was decided what could be done to ensure that it, and most of the rest of the waterfront, would not be inundated when the "big one" shook the city.

What to do about this perilous possibility set off another long series of studies, committees, hearings, recommendations, arguments, rebuttals, and delays. In April 2004, as part of an effort organized by the Seattle Department of Planning and Development, 22 teams -- about 300 people in all -- presented competing plans for a new waterfront. Despite this surfeit of opinions, there was good news for the aquarium: City officials insisted that every plan must include an expanded aquarium. It would not fall prey to waterfront redevelopment, but would become an integral part of it. In a massive, long-term project that, with the viaduct replacement, would cost billions, there was surely room for the relatively modest amounts needed to give one of the world's leading seaports one of the world's best aquariums.

Aquarium Makeover

With their hopes and plans largely captive to larger concerns, aquarium staff had to be content with improving what existed and continuing their efforts at entertainment, education, and research. In March 2005 Bill Arntz, acting director since 2000, retired and was replaced by John Braden, a veteran city official. That same month, a new sea otter pup was welcomed, the first member of the third generation of sea otters to come from the aquarium's breeding program.

Later in 2005, the city and the Seattle Aquarium Society announced a $37.6 million (later raised to $41 million) makeover of the facility and the largest expansion since it opened in 1977. Under the plan, the city agreed to pay to replace the pier's 760 decrepit wooden pilings with 270 new ones made of cement-filled steel, expected to last 50 years, and build a new platform atop them. The society would fund a floor-to-ceiling, 20-foot-high, 120,000-gallon fish tank near the aquarium's new entrance on Alaskan Way. To be called "Window on Washington Waters," it would feature fish and other marine life native to Northwest waters. The aquarium would also pay to remodel the entire east end of the Pier 59 building, tearing down most of what was there, rebuilding it, and reinstalling the original, restored façade, which had won historical-landmark status. The efforts were given a boost in June 2006 when the aquarium society received $1.5 million from the Bill and Melinda Gates Foundation, its largest contribution from a non-governmental source.

The work, which got underway in 2006, was characterized as the first phase of a larger project, and while it may have not been exactly what everyone wanted, the perilous condition of Pier 59 made quick action necessary. As an aquarium spokesperson explained, "uncertainty surrounding the seawall and replacement of the Alaskan Way Viaduct make it difficult to proceed with a major fundraising campaign" ("Aquarium Set for Makeover"). This difficulty was highlighted in September 2006, when the Seattle City Council approved a $6.3 million loan to the aquarium, repayable in 10 years, to allow the renovation and expansion to be completed despite a fundraising shortfall. 

The renovated and expanded portions of the aquarium opened on June 22, 2007, and featured, among other things, a new entrance hall, a cafe, an expanded gift shop, and an 18,000-square-foot auditorium space. The Window on Washington Waters addition was joined by another new exhibit titled "Crashing Waves" -- a 40-foot-long artificial-wave pool that held some of the aquarium's more durable starfish, anemones, and fish. Older exhibits, including the ever-popular otters and the underwater viewing dome, were where they had always been, although spruced up. It was far from the ambitious plan for an entirely new aquarium on piers 62 and 63 that had been killed by the overarching concerns raised by the Nisqually earthquake. But the improvements were significant, the crowds continued to come, and the aquarium remained in operational terms "just fine financially" ("Aquarium Shows Off New Views").

One other big change was soon to come. The partnership between the City of Seattle and the Seattle Aquarium Society that had operated the aquarium since the 1980s came to an end in 2010. In June it was announced that the society would take over virtually all of the facility's operations, allowing the budget-stressed city relief from its obligations while leaving with it the legal ownership of the building exteriors and the piers on which they sat. Although the aquarium was paying its own way (covering $10.7 million in operating costs in 2009), the agreement allowed the city to shed responsibilities such as IT support and contracting out the various third-party services the aquarium needed. Another consideration weighed in this decision: Private donors were hesitant to contribute to an operation so closely identified with city government, but were more generous when only a nonprofit foundation was the beneficiary. Seventy-five fulltime parks-department employees who worked at the aquarium were given five years to transition to the foundation, but for the public, the changes would be virtually invisible.

Planning for the Future

In late 2011 the Washington State Department of Transportation began preliminary work on a tunnel to replace the tottering Alaskan Way Viaduct, a mammoth undertaking that was to be done mostly with state and federal highway funds. In a largely advisory referendum, Seattle voters had approved the tunnel in August 2011, although the issue of the Alaskan Way Seawall, which presented far greater potential dangers, remained unresolved. But in the November 2012 election, 77 percent of Seattle voters approved $290 million in general-obligation bonds to replace the seawall -- the only thing preventing Puget Sound from reclaiming the waterfront, which was built almost entirely on fill from the Denny Regrade of 1897 to 1930.

Also in 2011, the Seattle Aquarium -- then the ninth-largest aquarium in the U.S., measured by attendance -- prepared its Strategic Plan to guide development through 2030. The plan had both aspirational and practical elements, but the aquarium's basic mission was simply stated: "Inspiring Conservation of Our Marine Environment" (Seattle Aquarium Strategic Plan, 2011-2030). Specific proposals included redeveloping the western (Elliott Bay) end of Pier 59 to open views and accommodate new exhibits; upgrading the structures and updating the exhibits housed on Pier 60; and expanding the footprint of the aquarium south from Pier 59 to allow for more exhibits and accommodate greater attendance.

From its inception in 1977 through early 2020, more than 27 million visitors passed through the aquarium's doors. The strategic plan estimated that annual attendance would grow to 1.1 million by 2020 and 1.5 million by 2030. Aquarium educational programs had drawn more than 2 million schoolchildren since 1977 and, in partnership with the University of Washington and funded by the National Science Foundation, the aquarium had been designated as one of the nation's 12 Centers for Ocean Sciences Education Excellence.

In 2013, construction began on Phase 1 of Seattle's $756 million Waterfront Plan under the direction of a newly created Seattle Office of the Waterfront. The seawall replacement, featuring light-penetrating blocks installed at regular intervals to help guide migrating salmon, was completed in 2016. Meanwhile, the aquarium continued to move forward with new and innovative programs. In 2015 it became a founding member of the James Beard Foundation's Smart Catch program for sustainable seafood, and in 2018 it created a new department, Conservation Programs & Partnerships, to bring new resources to field conservation efforts. Also in 2018, it gave its first lifetime achievement award to conservation icon Dr. Sylvia Earle and renamed its signature award, the Seattle Aquarium Medal, in her honor. 

At the Center of a Reimagined Waterfront

Seattle's Waterfront Plan, scheduled for completion in 2025, is one of the largest infrastructure projects in the city's history and has dramatically altered the face Seattle presents to the world. With the viaduct gone, the central shoreline no longer is cut off from the downtown core, making it more accessible to residents and tourists alike. The aquarium is an integral part of this massive redevelopment. In spring 2014, the Seattle Aquarium Society hired a lead architect, Marc L’Italien, principal of the San Francisco-based firm EHDD, and an exhibit designer, Tom Hennes, founder/principal of the New York City-based firm Thinc, to develop visions from the 2011 Strategic Plan. The aquarium's wish list included a 70-percent expansion that would provide room for new exhibits, additional educational facilities, and increased attendance.

The aquarium's expansion master plan was completed in 2015 and approved by the city council, but it took several more years before the final funding agreement was authorized. A central part of the plan was the Ocean Pavilion, a new facility across the street from the aquarium that is integrated into the new Overlook Walk connecting the waterfront to Pike Place Market. Schedule to open in 2024 at a cost of $160 million, the Ocean Pavilion will be home to a variety of sharks, rays, and other marine life in a 325,000-gallon tank. "Seattle Aquarium envisions that Seattle will be reconnected to the ecosystem of the Pacific Ocean through its new Ocean Pavilion – an investment that will help connect downtown, Pike Place Market and the waterfront as a gathering place for all ... It will provide several critical public features such as a new public elevator and a publicly accessible rooftop park that will connect to the Overlook Walk" ("Waterfront Projects"). 

While construction continued apace, the aquarium weathered the COVID-19 pandemic by connecting digitally with visitors after it was forced to close for 197 days in 2020 and again for long stretches in 2021. It instituted an "experience the Aquarium from anywhere" program and virtually hosted other programs and conferences, including the world's largest gathering of sea otter experts in 2021. Attendees celebrated Adaa, at age 22 the oldest northern sea otter in human care in the U.S. Adaa lived another year before dying of cancer in 2022. Meanwhile, the aquarium -- in operation for 45 years as of 2022 and on firm financial footing -- was poised to remain a vibrant center of entertainment, education, and scientific study for years to come.


"Waterfront Projects," Seattle Waterfront website accessed October 1, 2022 (; Daniel Beekman, "Seattle Aquarium Plans $113 Million Pavilion," The Seattle Times, December 9, 2019 (; Sarah Grace Taylor, "City to Lend $20 Million to Aquarium," Ibid., August 17, 2022; Bill Sieverling, "The Anatomy of Thrust Vote," Seattle Post-Intelligencer, February 15, 1968, p. 1; Bill Sieverling, "Stadium Wins, Transit Loses," Ibid., February 14, 1968; Mike Conant, "Mayor Sees Tragic Loss in Rapid Transit Defeat," Ibid., February 15, 1968; "The Triumph of Forward Thrust," Ibid., February 15, 1968; "Aquarium at Golden Garden OK'd," The Seattle Times, April 6, 1971, p. A-21; Don Page, "Dr. Ray Backs Aquarium Site," Seattle Post-Intelligencer, April 2, 1971, p. 15; Michael J. Parks, "Support Lost for Ballard Aquarium Site," Ibid., April 1, 1971, p. E-15; Sam R. Sperry, "Council Votes to Bar Aquarium at Golden Gardens Park Site," The Seattle Times, December 17, 1971, p. A-1; "Aquarium Petition Qualifies," Ibid., December 1, 1971, p. B-8; Sam R. Sperry, "Council Votes to Bar Aquarium at Golden Gardens Park Site," Ibid., December 17, 1971, p. A-1; Sam R. Sperry, "Aquarium to be Built at Piers 60 and 61," Ibid., July 4, 1972, p. A-10; "Pier 59 Now Favored for Aquarium," Ibid., October 29, 1973, p. B-7; "Top Award for Aquarium," Ibid., April 3, 1977, p. C-9; Maribeth Morris, "The Age of Aquarium," Seattle Post-Intelligencer, May 21, 1977, p. A-1; "1,524 Visit Aquarium on Opening Day," The Seattle Times, May 22, 1977, p. A-7; "More Than Predicted Visit New Aquarium," Ibid., September 23, 1977; Hill Williams, Hill Williams, "Salmon Splash Their Way Home to Aquarium; Experiment Works," Ibid., September 15, 1979, p. A-1; "Aquarium Exhibit Gives Feel for Marine Health," Ibid., August 14, 1986, p. C-1; John Hartl, "Pier 59's OmniRama Theater Eclipses Cinerama," Ibid., September 15, 1979, p. A-1; Hill Williams, "Revenue Loss: Aquarium Seeking New Director," Ibid., June 6, 1981, p. D-12; Joni Balter, "Waterfront Tab Gets Bigger," Ibid., August 14, 1986, p. E-1; Duff Wilson, "Seattle Aquarium Director Resigns," Ibid., November 10, 1984, p. A-3; Bob Lane, "County puts bond issue on ballot," Ibid., June 21, 1988, p. B-2; Bob Lane and Joni Balter, "A Big `No' from Voters," Ibid., September 21, 1988, p. B-9; Dan Coughlin, "Little Chance of New Vote on County Bonds to Buy Open Spaces," Seattle Post-Intelligencer, September 22, 1988, p. B-1; Jim Brunner and Justin Hopkins, "Lawmakers Kill Plan to Allow Tax Increase for Zoo on Ballot -- Heavey Leads Opposition in 24-22 Vote," Ibid., February 16, 2000, p. B-1; Beth Kaiman and Joshua Robin, "Aquarium Director to Resign -- 80-Hour Weeks Aggravated Health," Ibid., May 11, 2000, p. 85; Ross Anderson, "Divers to Take Octopus Census -- Aquarium Wants Count of Giants," Ibid., February 4, 2000, p. B-5; Frank Vinluan, "Swimming Toward Recovery -- Two Lost Sea Turtles Are Recuperating at Aquarium," Ibid., January 7, 2000, p. B-1; "Seattle Aquarium Appoints Acting Director," Ibid., July 19, 2000, p. B-3; Beth Kaiman, "Aquarium Architect Discloses Plans," Ibid., July 20, 2000, p. B-3; Beth Kaiman, "Views Prevail in Siting for Aquarium," Ibid., February 23, 2001, p. B-3; Susan Gilmore, "22 Ways to Do Waterfront -- Design Teams Come Up With Post-Viaduct Visions," Ibid., April 6, 2004, p. B-2; Susan Gilmore, "Aquarium Set for Makeover," Ibid., September 2, 2005, p. B-4; Haley Edwards, "Aquarium Shows Off New Views," Ibid., June 15, 2007, p. A-1; Sonia Krishnan, "Nonprofit to Take Helm at Aquarium -- Seattle Aquarium's Management to Change Hands July 1," Ibid., June 1, 2010, p. B-1; Seattle Aquarium Strategic Plan, 2011-2030, Seattle Aquarium website accessed October 24, 2014 (; "Quick Facts," Seattle Aquarium website accessed October 24, 2014 (; "Momentum Builds on the Expanded Aquarium," Currents, Seattle Aquarium newsletter, Fall 2014, p. 3; Joel Connelly, "Viaduct Tunnel Replacement Will Not Open to Traffic Until August 2017," Seattle Post-Intelligencer, December 22, 2014 (; Anna McAllister, email to John Caldbick, December 30, 2014, in possession of John Caldbick, Seattle. Note: This essay, originally written in 2000, was substantially expanded and updated on November 5, 2014. It was updated further on October 3, 2022. 

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