Over centuries, the vie cave were further altered by various empires, including the Ostrogoths, Lombards and Franks, that used them to suit their needs. At some unknown point along the way, stairs were added and ravines were deepened, but even the original vie cave had a way to channel out the rainwater: in each path I walked, I could see some form of water trough system cut into the tuff rock to prevent erosion and drain rainwater. "Etruscans were extremely skilled hydraulic engineers," Ronca said. "We know that they levelled some lakes and then drained huge wetlands in order to have lands that were possible to farm."