The Hotel Terme Millepini in Padua, Italy looks like any other resort. With palm trees, spas, gourmet restaurants, it's a little slice of heaven. Following a recent renovation, however, the hotel entered the Guinness Book of World Records. The record? World's deepest pool. After a few lessons from an in-house freediving expert, ambitious guests can attempt a descent below the surface, to reach the bottom of the Y-40 "Deep Joy" pool. At 40 meters, or 131 feet, the pool is as deep as a 14-story building is tall. Less courageous individuals can view the divers from several underwater windows, as well as a transparent tunnel that runs beneath the surface. The water is kept at a constant temperature of 34 degrees Celsius (93 degrees Fahrenheit), so there's never a need for a wetsuit, even way down below.