The best-known visible light telescope facility in Asia is probably the six-meter Bol’shoi Teleskop Azimultal’nyi (BTA, or “Great Azimuthal Telescope”), near Nizhny Arkhyz, Russia. The telescope sits atop Mount Pastukhov, about 90 miles (150 kilometers) south of Stavropol, between the Black Sea and the Caspian Sea. It has been operating since 1976, and for a time was the world’s largest telescope. For radio astronomy, the Giant Metrewave Radio Telescope near Pune, India, is an interferometric array of thirty dishes, each 148 feet (45 meters) across.