One of a number of interpretive displays at the Museum of Flight and inside the T. Evans Wyckoff Memorial Bridge reads:
The Birth of Boeing Field
Aviation Comes to the Northwest
The King County International Airport--commonly known as Boeing Field--lies along the original west bank of the meandering Duwamish River, just east of the Museum of Flight.
The spot now occupied by the Museum was, in the early 1900s, the location of the Meadows resort horse racetrack. It was over this racetrack on March 11, 1910, where Charles K. Hamilton became the first person to ever fly in Washington State.
In 1917, former lumber businessman William E. Boeing moved to an old shipyard building--affectionately known as the Red Barn--downriver (north) of this location to consolidate his new airplane factory. His planes had to be tested off-site due to the lack of a proper airfield nearby.
An Airport of King County
In 1920, the local government was straightening the Duwamish River with dredging and filling. Boeing's desires for a new aviation field coincided with the government's plan to build one to serve Seattle's growing population.
The eighteen feet of fill topped by cinders over farmlands on the floodplains of the Duwamish River was dubbed Boeing Field. The opening ceremony took place on July 26, 1928, with more than 50,000 people in attendance.
Boeing Field was used extensively right from the start. After its opening day, the airport was filled with planes, practically ending Seattle's geographical isolation from the rest of the country.