Ao no Doumon 3(Blue Cave Gate),
Representative scenic spot of Yabakei. Ao no Doumon (Blue Cave Gate), a famous scenic spot made famous by Hiroshi Kikuchi's novel Onshu no Kanatani (Beyond the Onshu), is a cave gate at the foot of Koshuho Peak, which rises above the Yamakuni River. It is also famous for its autumn foliage, which attracts many visitors every year.