Greenlake is a park in Seattle with a three mile walking and biking path around it. There are several sandy spots resembling “beaches”, docks, baseball diamonds and playfields, and a boat rental place. It is a great place to practice yoga because you don’t feel so exposed, what with everyone focused more on getting around the lake than people watching. You can practice in the sun or in the shade, near people or away from people, and different yoga teachers and organizations host outdoor, usually free, classes there in the summer.
I practiced on the east side of the lake, close to Tangletown. It was breezy, quiet, and the biggest distraction were the people jogging by on the gravel path next to the road. There is something about the continual movement of people in one direction that makes you feel like less of a spectacle.