The main entrance to Petra, in ancient times as in ours, is through the Siq (meaning "cleft"), a narrow, 1200-meter long canyon between towering walls of astonishing red and purple-hued stone. Bands of Nabatean paving stones are still visible along the way. Votive niches, some of which contain inscriptions dating from the 2nd and 3rd centuries AD, show that this road served as much as a ceremonial path as a passageway. Your first glimpse of the magnificent Treasury, after you've walked a hundred meters or so through the narrow Siq, will take your breath away. Film buffs may recall Harrison Ford galloping through this area in Indiana Jones and the Last Crusade.