Even when it's not 115 degrees out, we like to head underground to our favorite secret subversive hideaway, where we can relish the big-city vibe of an underground tunnel while also enjoying live music and public art, besides. And even though the Camelback Pedestrian Underpass isn't exactly a secret (it would be hard to hide a much-publicized passageway that runs under Camelback Road and connects two of the city's most popular dining and shopping destinations), we can't help feeling kind of like we're in on a special alternative-universe version of Phoenix, where we're watching a free performance in an underground subway station.Completed in 2007, this glorious, 86-foot-long pedestrian underpass just east of 24th Street on Camelback provides safe passage for people moving from, say, the condominiums and office park at Esplanade Center to the shops and restaurants at Biltmore Fashion Park. Seen from the street, the underpass looks like a bump in the road with nice xeriscaping on either side. Down below you'll find decorative pavement, lush landscaping, and rubberized asphalt to minimize noise and increase proper air circulation. But the real secret to the well-lit tunnel's success is its otherness: We feel as if we've wandered onto the platform of an especially glamorous subway stop, where we always linger to read the pamphlets being passed out by a city-wise political activist or enjoy the music of one of the several musicians who perform there from time to time. We gaze at the lovely terrazzo mosaic and pretend we're in the big city, where one can go briefly underground, only to emerge at the other end having enjoyed getting to where we're going.