Joined the Tokyo Speleo club (http://www.tokyospeleo.jp) for a visit to Rokon Do (waterfall view) and Sora Ana (sky) cave, Iwate prefecture, in frozen north of Japan. Mission was to survey and photograph cave (incl new passage) on behalf of cave owner who is re opening cave as show cave with the coming of a new highway nearby thats hoped will increase visitors from current dwindling < 7,000 per year to previous 70,000 per year record.

Due to start of cave being a show cave we started caving at 8pm at night so as not to bother tourists. Caving through the night, teams emerging at 4am following day.

Team made up of Japanese cavers Minato Koei, Goto Satoshi, Nakagomi Yukiko, Kurisu Ryuichi, Noike Kohei, Miyazaki Tomohiko, Makisima Keiko, Kikuchi Toshio, myself and German caver Dr Joerg Dreybrodt.

Sora Ana cave is quite an interesting cave with a number of very tight sections. Most of cave wall is stained black from steam train soot that used to leak into and fill the cave years ago from nearby train tunnel. We heard modern passenger train passing at one point through nearby tunnel. The larger nearby Rokon Do cave is a stream-way cave with beautiful tall narrow meanders and a 30m waterfall (that marks the end of show cave and start of our exploration. A new higher level passageway was discovered and teams surveyed a few hundred meters of it during this expedition.

Many thanks to the team especially to Goto san for helping with the arrangements.