These tubers from 1953 were all members of the Seattle Tubing Society.
Clearly they knew how to have a good time and look stylish even on the water. I love the guy with the top hat way in the back.
From the 3.2 minutes of research I did on this photo it's the Sammamish Slough floating down to Lake Washington in Seattle.
Professional photographer, Burt Glinn (who died in 2008) shot the photo along with several others here.
Photo credit: burtglinn.com