Hard-packed dirt. This is not a sanctioned city park, but a rare, abandoned corner of the city. Be mindful of dogs and their peoples, as well as cats, bunnies. I used to see a pet rabbit down there that belonged to a teammate of mine who lived up above. There may be access to Swan Island from here, via the steeper descent from this triangular trail network, and might serve as part of the legendary off-road Northern Passage (is there such a thing?).