Kitt Peak is the largest collection of optical and radio telescopes in the world, 56 miles southwest of Tucson on the Tohono O'odham reservation. The drive up is dramatic in itself — winding switchbacks through saguaro forest, with the desert basin getting wider with every turn.
The visitor centre offers daytime tours of three of the telescopes, including the giant Mayall four-metre. The real reason to come is the nightly observing programmes: meet at sunset, take a guided tour of the constellations on the summit, then spend a couple of hours looking through the smaller research telescopes at galaxies and nebulae. Book in advance; bring a warm jacket even in summer — the elevation is 2,100 metres and nights are cold.