Want to get fit super fast? Come to Bhagsu (India) and stay in a hotel at the top of the hill, near Singh Corner. Whatever you do, shopping, eating, even just wandering around, you have to walk up the extremely steep hill at least a couple times each day. The thin mountain air makes breathing just that little more difficult. 10 steps and your chest'll be heaving. By the time you leave you'll be fit enough to run a marathon.