Been to Mitake, it's just one boulder really, but excellent. Took me three hours to get there on the train from Funabashi though. There was a keen young man camping under the station platform, to beat the inevitable crowd (this being the closest 'real climbing' to Tokyo). Some reasonable warm ups, a couple of good 7A/Bs, but best problems are a couple of 8As (three dan, in the local grades). Got a bouldering guide from Muroi Tokio (of 8c slab fame) at the Funabashi wall. It has Ogawayama and Mitsumine in it too and it's all in Japanese. I have another guide which is mainly routes and it's written by Kitayama Makoto. Came from an outdoor shop somewhere in Japan (Kobe, I think). It has a good-looking section on Ogawayama, with some good maps and inspiring photos; all in Japanese again. You'll probably need a car to get to Ogawayama or Mitsumine. Best conditions in Mitake in the depths of Winter, in Ogawayama in Autumn, since I believe it lies under snow in Winter.
Worth the effort for Mitake though (I think that's the name of the station you have to go to), fairly off the beaten track for Tokyo. Kanbate.
