Apart form the Charles Bridge, Radost FX is the most talked-about evening destination in Praha. There's a café with castle-like upholstery, a restaurant that manages to feature vegetarian selections from Italy, Mexico, China, Thailand and America in one heavy wooden menu, and a club whose widespread cushions seem to be thinking nasty thoughts. Radost means joy in Bulgarian and pleasure in Czech, so you do the math. Local and international DJs. Hip-hop, R & B, the works. Open 10 PM to 5 AM. Free English movies on Mondays. Belehradska Street . Metro A: I.P. Pavlova.