Clinging to the mountainside, the Inca steps snake up, down, and around the Andean mountains. A carefully-designed drawbridge guards the western entrance to Machu Picchu. The control mechanism is a simple wooden plank that covers a large section missing from the bridge. It's mostly absent of railings so don't look down unless you love heights. Those of you who don't are likely to experience quivering knees at the sight of the 1,900 foot drop.