On November 20, 1970, the United States Department of the Interior names Marymoor Prehistoric Indian site as a Registered National Historic Place, site No. 70000642. Evidence unearthed during a six-year-long archaeological excavation indicates that the site may have been used as a seasonal camp as early as 3000 or even 4000 B.C., and as a more substantial campsite around 1000 B.C.
Marymoor Park was purchased by King County in 1962. The park was best known from its days under the ownership of James Clise, who turned the property into a working farm of world renown. Clise sold the property in 1928, after which it passed through various hands until being bought by King County.
From 1964 to 1970, an archaeological dig was undertaken at a small part of the park along the Sammamish River. The project was under the direction of Dr. Robert E. Greengo, an archaeology professor at the University of Washington, and also adjunct curator of New World Archaeology at the Burke Museum on campus.
Spanning the Ages
Four separate sites near or in Marymoor Park were considered as archaeological sites, but only one was chosen for the dig. During the process, it was discovered that there were two separate occupations of the chosen site, separated by 3000 years of time.
The older part of the site may have been visited by Indians as early as 4000 B.C. Evidence for this is found in stone tools made of basalt, and especially in bipointed projectile points indicative of that era. Evidence suggests that hunters and gatherers used the site only seasonally.
Around 1000 B.C. the site may have seen more substantial occupation. Stone tools found from that era included projectile points, scrapers, choppers, and small blades. The raw materials for these tools included quartz, jasper, chert, chalcedony, and obsidian. Many of these stones were not native to the valley, indicating that the inhabitants may have had connections to Eastern Washington.
When the first white settlers arrived in the valley in the 1860s, only a few small camps of Indians were present. These were made up of the Sammamish band of the Duwamish Indian tribe. No link has been established between these inhabitants and earlier prehistoric dwellers.
After King County bought the park, the Clise mansion was converted into use as Marymoor Museum. Some of the 1,000 artifacts unearthed during the archaeological dig were displayed there, while many others went into the collections at the Burke Museum. The Marymoor Museum operated out of the mansion until 2002, when King County underwent a budget shortfall and evicted it.
Early in 1970, the excavation site was nominated to the National Register of Historic Sites, along with other King County sites including Seattle’s Pike Place Market District, the Pioneer Square District, Boeing Aircraft Company Building number 105 and the schooner Wawona. Marymoor’s selection to the register makes it one of the few prehistoric sites in the county noted as such.