Originally Posted by
AlwaysAisle
Kusatsu Onsen (草津温泉) in Gunnma.
Yunishigawa Onsen (湯西川温泉) in Tochigi.
Both I went by car. Trains do not run directly to those areas so car is bit convenient. Both 1 night road trip distances from Tokyo. Yunishigawa Onsen is more rural than Kusatsu Onsen. Mentioned being at Izu peninsula, but was it eastern coast of Izu peninsula? Western coast of Izu peninsula has some onsen also. There is no train service at western coast of Izu peninsula and car is convenient for western coast of Izu peninsula.
Yes it was the eastern coast, which I accessed by train. You're right, I should consider the western coast. The ocean views were great.