In 2008, during a routine archaeological survey conducted as part of a stream restoration project, stone artifacts were discovered at Bear Creek, between Marymoor Park and the nearby Redmond Town Center shopping mall. In 2009–2014, more artifacts were discovered beneath a layer of peat, including stone flakes, scrapers, awls, and spear points. An announcement was made in 2015 that they were the oldest stone tools discovered in Western Washington after the peat was determined by Carbon-14 dating to have been deposited 10,000 years ago.