San Francisco's Recreation and Parks Department takes care of big things like Golden Gate Park, Dolores Park, several golf courses, and a marina, as well as medium-sized things such as Alamo Square, Alta Plaza Park, and Lafayette Park.
Then there are the mini parks, nameless patches of green that turn up in residential neighborhoods inviting the passerby to pause and take a breath before moving on.
This one occupies about two building lots. On the left of the photo you see the wall of an adjacent house. to the right, just out of view, is the small Victorian house I wrote about recently. In fact, you can see a bit of this park in the photo of that house.
Though I have no credentials in landscape architecture, I will say these mini parks seem to be little masterpieces of design. In the photo you see a densely planted area. It has a path meandering through it. Behind me as I took the photo, the rest of the park is a a sparsely planted shade garden beneath mature trees.
I found no list of mini parks on the website for Recreation and Parks, but a search for "Mini Park" turned up a long list of articles about individual minis. The variety is amazing.