The Cerro Tololo Astronomical Observatory is located about 500km north of Santiago, Chile, about 70km east of La Serena, at an altitude of 2200 meters.
Coordinates: W 70d48m52.7s S 30d09m55.5s
Telephone: 011-56-51-225415
Fax: 011-56-51-205342
Post: CTIO Support Office CTIO/AURA Inc.
950 N. Cherry Ave. (or) Casilla 603
Tucson AZ 85719 La Serena, Chile