Grottes et karsts de Chine
Sur les traces de Xu Xiake

4.4 Fong Yen

Zone 48 - 642946 2748748 Alt 1114m

Survey contains 46 survey stations, joined by 45 shots.

There are 0 loops.

Total length of survey shots = 1120.80m (1120.80m adjusted)

Total plan length of survey shots = 967.51m

Total vertical length of survey shots = 410.60m

Vertical range = 407.67m (from fong_yen.gps at 1114.00m to fong_yen.r1 at 706.33m)

North-South range = 592.86m (from fong_yen.r1 at 2749340.86m to fong_yen.gps at 2748748.00m)

East-West range = 239.60m (from fong_yen.r2 at 643054.73m to fong_yen.p22 at 642815.14m)

1-nodes (qty 2) 2-nodes (qty 44)

This is essentially a 400m deep canyon that could be a tributary of a large river system. It starts by descending heavily vegetated slopes and walls before joining the huge canyon, which is shadowed by jutting roofs. There was very little water present other than pools, but this is clearly an active system judging by the clean water-washed walls. No obvious camp or safe area found so far, that would provide a refuge in flood conditions. It was explored over a 3-day period, to a point where daylight was lost and we ran out of rope. 500m of rope is required to this point. The way on is open apart from a small pitch, but given the hostile nature of the passage, future exploration will be very committing. There was no evidence of previous exploration.