Went to 81 for an easy day to tick off the crap lead near the RH route from 81b. To me it looked like a tight, loose & awkward route through a boulder choke that obviously didn't go. Only went in cos Olly thought it was "interesting". Having moved the loosest rocks out of the way I wriggled through and it opened up into a rift. The boulders looked less bad from below, so Olly came through as well. Got into a rift with various holes in the floor to a lower passage in the same rift. I traversed right to the end to where it was easy to climb down. This got us down to the top of a lot of ice which formed a floor to the rift chamber. Walked carefully around on the ice we saw some cool curved ice formations. At the end of the ice there appeared to be a pitch down between the ice and rock. We were without gear so steered clear, but hypothesized it might drop into the ice castle passage in 148. Surveyed out (checking that the outer lead didn't do anything interesting)..