The main waterfront trail route along Puget Sound in Seattle is the Elliott Bay Trail, a scattered collection of trail segments that run from Century Link Field in the south to Smith Cove in Magnolia to the north — about 7 miles in total.
There are various running options here. The nicest section is 1.5 miles one-way from Olympic Sculpture Park north past the Seattle Center, home to the Space Needle, on through Myrtle Edwards Park. The Myrtle Edwards Park portion has particularly nice scenery and includes a paved trail, limited street crossings and a flat run. It is also possible to continue along the trail, which is scattered in segments, about 3 miles to Smith Cove in Magnolia. Alternatively, the trail continues south to CenturyLink Field.
Additional Options North: 3 miles from the fountain to the exit in Magnolia
Additional Options South: 2.8 miles from Olympic Park to CenturyLink Field