Atami Onsen, located in Shizuoka, Japan, has been a hot spring haven since ancient times. Even the famous shogun Tokugawa Ieyasu was so hooked on its healing waters that he tried to replicate them back in Edo (now Tokyo). With both indoor and outdoor baths to soak in, delicious seafood to savor, and attractions like Atami Castle for stunning views, this seaside town is a perfect spot for a relaxing getaway. Don't forget to try the local specialty, onsen manju sweet dumplings, before you leave!