EGYPT // Karnak is architecture on steroids. The Valley of the Kings  may have thrashed it on this list but, for most Luxor visitors, Karnak  gets equal billing. To the ancient Egyptians, this enormous religious  complex of temples and sanctuaries, decorated by soaring obelisks,  towering statues and mammoth pylons, was the earthly home of the god  Amun-Ra. A roll call of Pharaohs from the New Kingdom's 18th to 20th  dynasties have left their mark. These days the hypostyle hall in Karnak's  Amun Temple Enclosure, with its forest of 134 papyrus-shaped columns,  still stops people in their tracks as they contemplate its immense scale.  Arrive early (it opens at 6am) to get a good couple of hours exploring  before the 21st century intrudes in the form of tour buses.