Natural hot springs are highly popular through out Japan.Every region of the country has its share of hot springs and resort towns, which come with them.There are lots of minerals that distinguish and dissolve in the water which makes it relaxing. Although there are hundreds of hot springs across Japan, make sure you check out the ancient hot spring waters of Kusatsu Onsen. These are known to be Japan’s best and most effective.  Much of the resort’s water bubbles up in the yubatake (“hot water field”) in the town center.