who were these tombs built for?
For the pharaohs and powerful nobles of the New Kingdom
Valley of the Kings
 for the pharaohs and powerful nobles of the New Kingdom 
map of tombs in valley of the kings In 1799, members of Napoleon's expedition to Egypt (especially Vivant Denon) drew maps and plans of the known tombs, and for the first time noted the Western Valley
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Valley of the Kings [SEP] Introduction
The Valley of the Kings ( ; ), also known as the Valley of the Gates of the Kings ( ), is a valley in Egypt where, for a period of nearly 500 years from the 16th to 11th century BC, rock-cut tombs were excavated for the pharaohs and powerful nobles of the New Kingdom (the Eighteenth to the Twentieth Dynasties of Ancient Egypt). The valley stands on the west bank of the Nile, opposite Thebes (modern Luxor), within the heart of the Theban Necropolis. The wadi consists of two valleys, East Valley (where the majority of the royal tombs are situated) and West Valley.