It's not really open to the public ("trespassing" would be the official term here), but if you're willing to crawl under a chain-link fence and brave some pigeon poop, that yellow, vine-covered building on Airport Way South is an urban spelunking site worth seeking out on a Sunday afternoon. Three street artists have taken over the space?NKO, No Touching Ground, and Dan Hawkins?and though their work is the reason this place is on the map, one could argue that the building itself, collapsing under the heft of its own neglect, is the real destination. There are lovely bits of blurry spray paint and a graveyard-like installation of pallets overseen by No Touching Ground's owls, but what caught my eye was the detritus: a colorful tangle of old electric wires, the '70s-era sanitary-pad machine, and a roomful of turquoise lockers with calligraphed name tags. Yellowed, hand-marked attendance cards, a moss-carpeted room, and vast quantities of red and green traffic-light lenses are some of the finds you'll stumble across. Just don't tell anyone we sent you. ?Adriana Grant