San Pedro de Atacama lies 1674 km, or a little more than a thousand miles north of Santiago, the country's capital. While it is normally accessed by domestic non-stop flight to Calama, and a shuttle ride from the airport about 100 km (60 miles) to the town itself, it is also possible to take a bus to San Pedro from either the north or south of the country, though distances are long, and you may wish you'd flown.
The town is a small, 3X4 block area of adobe dwellings and mostly unpaved streets, in which a variety of lodging fits (and spills into the surrounding residential areas), and resturanteurs stand outside touting their many offers. But the truth is, nobody comes to San Pedro de Atacama for the town. The town was created due to its location near an oasis, but people come from all over the world to see the moonscapes, the jagged rocks, the dunes, the salt lakes, the ancient ruins, not springs,the llamas, the geysers, the flamingos, the vizcachas, the colored lakes, mountains to climb, the moonrise, the brilliant sky and many other attractions this area has to offer.
But the town is where nightlife happens, and although between the altitude and the extreme dryness (the Atacama desert is the driest in the world), you probably won't want to tie one on too heartily. In fact, though the town has a relaxed, nearly bohemian vibe, with earth toned sweaters and metal and leather jewelry for sale, but by about 10 PM, most of the party atmosphere is gone, and the city quiets down. Wintertime temperatures drop quite sharply, and from May through August the nights can be quite cold. Hight season is during Chile's national holiday (September 18th and surrounding dates) and when school is on holiday, January and February.