Valley of the Kings rains. There is currently little year-round rain in this part of Egypt, but there are occasional flash floods that hit the valley, dumping tons of debris into the open tombs. The quality of the rock in the Valley is inconsistent, ranging from finely-grained to coarse stone, the latter with the potential to be structurally unsound. The occasional layer of shale also caused construction and conservation difficulties, as this rock expands in the presence of water, forcing apart the stone surrounding it. It is thought that some tombs were altered in shape and size depending on the types of rock the
Valley of the Kings the actual tomb of Tutankhamun (KV62) in November 1922. Various expeditions have continued to explore the valley, adding greatly to the knowledge of the area. In 2001 the Theban Mapping Project designed new signs for the tombs, providing information and plans of the open tombs. The earliest tombs were located in cliffs at the top of scree slopes, under storm-fed waterfalls (KV34 and KV43). As these locations were filled, burials descended to the valley floor, gradually moving back up the slopes as the valley bottom filled with debris. This explains the location of the tombs KV62 and KV63 buried in