Grottes et karsts de Chine
Sur les traces de Xu Xiake

Liang Feng Dong (Dapo)- ‘Concrete Cave’- 25.277503°, 105.511657°

Concrete Cave is situated by the road opposite a hydro-electric station and between a number of road-side quarries and a cement works. It is at the level of the road and a concrete surface has been laid in the entrance for 10 metres. The entrance passage is roughly 7 metres high and 10 metres wide and is followed over a boulder strewn floor for approximately 170 metres to a large junction, the boulders having largely given way to a mud covered floor. In the right hand wall there is an oxbow passage of approximately 70 metres (not surveyed as the batteries had gone on the disto and our time was up). At the junction, the large passage to the left is followed for 180 metres over mud banks and past a pool to where the passage narrows and is blocked with mud.

To the right at the large junction the passage is followed almost entirely on mud-banks for 200 metres to a large drainage channel in the mud, about 5 metres deep, dropping into a muddy boulder plug. The passage can be followed up-stream on the mud-banks above the channel but these soon narrow and a slide down into the channel is necessary to reach the end in a large mud lined bowl after 150 metres. The way on from here is up the mud-slope at the back of the bowl to a mud-ridge at 6 metres, the passage beyond drops to a pitch that requires tackle to descend.