If you're going on an art walk, it helps when the galleries are actually within walking distance of one another. Minna Street, the SOMA alley between Mission and Howard, has long been the home of gallery-cum-club 111 Minna (111 Minna at Second St., 974-1719, www.111minnagallery.com). Since 1993, the brick space has been ground zero for international and local street and urban artists. In the spring, 111 Minna helped Last Gasp comics celebrate its 40th anniversary. Newer neighbors Catharine Clark Gallery (150 Minna at Third St., 399-1439, www.cclarkgallery.com) and Baer Ridgway Exhibitions (172 Minna at Third St., 777-1366, www.baerridgway.com) focus on contemporary art with cutting-edge shows. Baer Ridgway, which recently hosted selections from the collection of Steven Leiber, including pieces by Yoko Ono and Tom Sachs, doubles as a specialized bookstore in its basement. Catharine Clark Gallery offers a variety of new media pieces and often has discussions with the artists, as with Anthony Discenza's February talk on his solo exhibition, "Everything Will Probably Work Out Ok."