Mount Iwadono is located in the Nigioka-machi (town) district, the city of Otsuki, in Yamanashi Prefecture. Because of the proximity to JR Otsuki Station, it is a popular hiking destination. However, the Hatakura trail is the only one which reaches the top of the mountain right now. The other two trails, the Kowaze trail and the Iwadono trail, are closed due to rockfall. It takes about 20 minutes from Otsuki Station to the entrance of the Maruyama Park on foot, another 20 minutes to the Hatakura trailhead and about 40 minutes to reach the top of Mount Iwadono. The height of Mount Iwadono is 634 meters above sea level and it is the same height as Tokyo Skytree. However, the difference in elevation of Mount Iwadono and Otsuki Station (elevation: 358m) is 276 meters; therefore, it is not very hard to climb it. You can enjoy unobstructed views of Mount Fuji from there.
https://www.yamanashi-kankou.jp/english/discover/mount-iwadono.html; https://otsuki-kanko.info/blog/view/28097
Views from Mount Iwadono, Nigioka-town, Otsuki-city, Yamanashi, 01/05/2024
A limestone cave, the stone house of the ogre, where the ogre of Mount Iwadono was imagined to live, Nigioka-town, Otsuki-city, Yamanashi, 01/05/2024
A shrine at the side of the Hatakura trail to Mount Iwadono, Nigioka-town, Otsuki-city, Yamanashi, 01/05/2024