There are about 12 rivers running from Sanya urban area into the sea. The underground water is about 142 million tons. Sanya has very rich Geothermal heat resources, among which the most famous one is the Nantian Hotspring in the suburban area. You can even have hotspring SPA in a place in the urban area of Sanya. The hot springs in Sanya boast high mineral content and can exert therapeutically effects that can relieve or restore people's health.