Where: Royal Gorge, Colorado, over the Arkansas River.
Stats: 1,053 feet over the gorge; 1,260 feet long.
Awe Factors: Built in 1929 in six months by mainly inexperienced men, this bridge was an impressive feat of construction for its time. Wires were connected at the bottom of the gorge and pulled up the granite canyon despite gusty winds. In 1982, the bridge underwent a refurbishment, and wind cables were added. If looking straight down 1,000 feet isn’t scary enough, “the bridge rolls like waves,” said Peggy Gair, public relations manager for the Royal Gorge Bridge and Park. “It bends and sways a little—and it should. The flexibility is its strength.”