Chelva (Spain)

Chasm at Corta

Detail of the deep chasm that was made for the construction of the aqueduct, looking west. The excavation was made in a similar way on both sides of the mountain, but the central section has not been excavated but operates as a tunnel of 15 roman feet long. It may at first seem puzzling that the effort was made to make such a beautiful straight cut, and then not excavate the central part. The reason is probably that the rock was needed anyway as ashlars for the adjacent aqueduct bridge, but if the central part had been excavated as well, the resulting chasm would probably have become instable and could have collapsed into the aqueduct. In a normal quarry, one would not have worried about this but the roman engineers probably realize that this was the cheapest, fastest and safest solution; and it is still standing after nearly 2000 years !