I was at friend's soccer game in San Francisco and after it was done, I noticed that I was a couple of blocks away from the Great Highway. The Great Highway is a road that is about 3.5 miles in length and on the cities western edge. It was built in 1929. Since last year about half of it has been closed to traffic and I walked part of that section.
And there are cool benches that you can sit if you are tired: