Luxor is a modern city in Upper (southern) Egypt which includes the site of the Ancient Egyptian city of Thebes. Luxor has frequently been characterized as the "world's greatest open-air museum", as the ruins of the Egyptian temple complexes at Karnak and Luxor stand within the modern city. Immediately opposite, across the River Nile, lie the monuments, temples and tombs of the west bank Theban Necropolis, which includes the Valley of the Kings and Valley of the Queens. Thousands of tourists from all around the world arrive annually to visit Luxor's monuments, contributing greatly to the economy of the modern city.