Luxor in 3 days: where more than a third of the world's ancient monuments are concentrated in one city, where 63 royal tombs are carved into a natural pyramid-shaped mountain, where the Hypostyle Hall of Karnak has 134 columns as tall as a 7-story building, where Howard Carter found 5,398 objects in Tutankhamun's tiny tomb in 1922, and where 80 hot air balloons fly simultaneously above the Valley of the Kings every dawn.