🌊 Duwamish River

The Duwamish River runs north for about 11 miles (18 km) through the cities of Tukwila and Seattle in the US state of Washington before emptying into Elliott Bay on the Puget Sound. Historically, the river formed from the confluence of the White and Black rivers in what is now Renton, but human modifications in the early 20th century led it to become the lower portion of the Green River. During the Last Glacial Period, the Duwamish Valley was carved out by glacial meltwater from the advancing Cordilleran ice sheet, forming what was initially an inlet of Puget Sound, which was later filled by the eruption of Mount Rainier and the Osceola Mudflow around 5,600 years ago.