If you're seeking an unusual and invigorating (notice I didn't necessarily say relaxing) spa experience, an authentic Turkish bath in Istanbul is sure to deliver. A little soap, a little submission and a little Islam make for an unlikely combination but a terrific cleanse as your rest on a grand marble slab, feel the sun slide through the ceiling holes to your soul and let a stranger loofah your skin till it sheds. Sound painful? It is. But when you rise to rinse it will be well worth it. Ask any hostel (I recommend the Orient) in Istanbul and they'll be glad to set it up for you. Women and men bathe separately, knickers are optional and if you forget the tip, don't worry, the bather will remind you.