2026 Onogawa Onsen Starry Sky Full-Day Course

Onogawa Onsen (小野川温泉) in Onogawa-machi, Yonezawa City, Yamagata Prefecture, is a hot spring town described on Yonezawa City's official website as a place where you can enjoy 'a duet of starry skies and fireflies.' It is dark enough to be certified by the Ministry of the Environment as a 'Furusato Ikimono no Sato' (hometown wildlife habitat), and is about a 20-minute drive from the city center. Some inns offer day-trip bathing, but hours vary by facility, so please check directly with each inn. Since this is not a dedicated observatory or viewing facility but rather a spot to look up at the night sky from the streets of the hot spring town, there is no admission fee or gate opening/closing time. However, as this is a residential and inn district, please be considerate of neighbors and enjoy the view quietly at night.