Karst holes 14.09.11.Iz due sinkhole blocked traffic on the street Pasha Savelevoj in Tver. The main problem is that the accident happened in the area in the middle…

Karst holes The failure on the road in the city of Chongqing. Photo from epochtimes.com 3.01.11.Proval length of 70 meters and a depth of about 3 meters was…