At 1,126 meters in height, the seven peaks of Mount Sanbe make it the highest point in Iwami. There have been minor eruptions of this volcano in historical times, but somewhere between 3,500 and 3,750 years ago there was a major eruption.
A few years ago, while working on some rice paddies to the north of Sanbe, the topsoil was excavated away to reveal the top of an ancient tree buried during that eruption. Further excavation revealed a total of 30 trees that had been lying under the rice paddies, buried by the eruption.
The Sanbe Azukihara Buried Forest park shows some of the trees exactly as they were left after the volcanic activity. One can descend 13.5 metres below ground level to see them in-situ.
The biggest tree has a base of 1.8 metres, and the oldest tree has 636 tree rings making it easily more than 4,000 years old. The trees are Japanese Cedar.
One of the tree bases has its own building, and it feels like entering a missile silo.
The park and museum is located on the north side of sanbe, about 20 mins by car from Oda Station on the JR Sanin line. Like a lot of interesting sites "off the beaten track" there is no public transport that reaches it. Open Tue through Sun, year round, with several short breaks, so best to phone to make sure its open. (0854) 86 9500
Entrance Adults: 300yen, kids: 100yen