The crater is approximately 70 meters deep and contains a small shrine dedicated to Sengen-dai-myojin.
Unlike most volcanoes, the slope angle is uniform at approximately 30 degrees due to the specific composition of scoria (cinder).
The mountain was formed roughly 4,000 years ago during the most recent volcanic eruption of the Omuroyama group.
The annual Yamayaki fire festival has been practiced for over 700 years to preserve the mountain's treeless, grassy appearance.
The base of the mountain serves as the geological center for the Izu Peninsula UNESCO Global Geopark.
Mt. Omuro is a 580-meter extinct cinder cone volcano in Itō, recognized as a Natural Monument of Japan. The mountain features a distinctive grass-covered, bowl-shaped crater approximately 300 meters in diameter. Access to the summit is provided exclusively by a single-person chairlift system. Visitors can walk the 1-kilometer circular path around the crater rim, which offers views of the Izu Peninsula and Mt. Fuji on clear days. The crater floor serves as a facility for archery, where targets are set up for public use. The grassy exterior is maintained through 'Yamayaki,' a traditional controlled burn conducted annually in early spring to prevent forest encroachment. Paragliding operators utilize the slopes for flight activities throughout the year, weather permitting.
The highest point on the southern side of the rim, offering a panoramic view that includes the crater bowl and Mt. Fuji in the distance.
The wind on the crater rim is significantly stronger than at the base; bring a windbreaker even in mild weather.
Check local wind conditions online before departure, as the chairlift operations and paragliding activities are frequently suspended during high-wind events.
Wear closed-toe athletic shoes with good traction for the gravel-heavy walking path around the crater.
Attempting to hike up the mountain on foot, as climbing the exterior slopes is strictly prohibited to protect the vegetation.
The chairlift suspends operations during high winds or severe weather; the annual Yamayaki burn typically occurs in February.
Stay strictly on the designated walking path to prevent soil erosion on the steep crater walls.
