Long before the Jacuzzi brothers introduced hot tub to the world, many such natural huge tubs existed in the world. They were created nearly 20-45 millions of years ago, when the surface of the earth was ridden by terrifying volcanoes. Propelled by the geothermal heat, the bubbling hot water in the springs are rich in minerals which can be used therapeutically to cure many illnesses. These amazing hot springs are found all around the world, even under the seas and oceans. Some of them can reach temperature of 350°C which off course is not fit for a soothing bath. Here is the list of 10 natural hot springs of the world which are quite famous, though not every one of them is good enough for a dip.