| Mount Iō | |
| Other Name: | 硫黄山 |
| Elevation M: | 1562.0 |
| Elevation Ref: | [1] |
| Prominence M: | 243 |
| Parent Peak: | Mount Sashirui |
| Map: | Japan |
| Label Position: | left |
| Listing: | List of mountains in Japan List of volcanoes in Japan |
| Translation: | Sulphur Mountain |
| Language: | Japanese |
| Location: | Hokkaidō, Japan |
| Range: | Shiretoko Peninsula |
| Coordinates: | 44.1333°N 145.1611°W |
| Topo: | Geospatial Information Authority, 25000:1 硫黄山 50000:1 羅臼 |
| Type: | Stratovolcano |
| Volcanic Arc/Belt: | Kuril arc[2] |
| Last Eruption: | 1936 |
also Mount Iwo is an active andesitic stratovolcano on the Shiretoko Peninsula of Hokkaidō, Japan. It sits within the borders of the town of Shari. Mount Iō is known for erupting liquid sulphur in the eruptions of 1889 and 1936.[3] Mount Iō literally means, sulphur mountain. There are two explosion craters and a lava dome at the summit of the volcano.[4]
Volcanic activity started at least 240,000 years ago.[4] Mount Iō has erupted at the following times:[5]