Best Power Walk

Why endure the company of sweating cell-phoners in some overpriced gym when you can raise your heartbeat climbing over San Francisco's well-oxygenated, vista-blessed, practically perpendicular hills, free of charge? Begin your hourlong trek at Jones and Filbert. Head south up the horrible two blocks of Jones to Green and take a right. Head west on Green for the 12 easy blocks to Fillmore, then go left up Fillmore to Vallejo (a brutal stretch), turn right, and tackle the increasingly unpleasant five blocks to Broderick. Go left on Broderick one block to Broadway, take a left and head east. The next 18 blocks highlight two stretches -- Pierce to Fillmore and Larkin to Jones -- that are, to the uninitiated, appalling. Finally, take a left on Taylor for one last block of horror (to Vallejo) and continue three more blocks north to Filbert, one block east of your starting point.