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
Victims of Terrorist Attack on the Pentagon Memorial passengers and six crew members aboard American Airlines Flight 77 (which crashed into the building) are inscribed on the memorial. After the 2001 terrorist attack on the Pentagon, Arlington National Cemetery Superintendent John C. Metzler, Jr. realized that there was a strong likelihood that many of the victims might not have their remains identified, while other remains might be commingled. Many of the victims would be military personnel whose families could choose to have their loved ones buried at Arlington. This would necessitate a group burial at the cemetery, and an appropriate monument to mark the grave. Metzler designed the