Years ago there was a funky little gym in Emeryville called CityRock that catered to the rock-climbing elite: guys who lived out of Volkswagen vans, rarely showered, and had arms that seemed to hang down to their knees. In 1999, it transformed into Berkeley Ironworks, an 18,000-square-foot warehouse with an impressive weight room, saunas, spinning and yoga classes, and a clientele that includes both extreme-sport professionals and beginners. Walk in the front door and what rivets your attention first are the 45-foot walls, towers, overhangs, and chimneys. With one quick, easy lesson (given daily on a drop-in basis), you'll soon be climbing with the big boys, though maybe not so high or quite so vertically. Now here's a chance to do something in southwest Berkeley that you may have only read about in Outside magazine or seen through binoculars in Yosemite.