RATAN-600: the World´s biggest reflector at the ´cross roads´

The RATAN-600 new-technology telescope, which supplies about one-quarter of the observational material in Russia in the field of radio astronomy and more than 80% in the central, centimeter-decimeter range, is described. The RATAN-600 is the first multi-element-reflector radio telescope without any structure linking the surface elements. The functions normally performed by such structure are executed by the Earth´s surface. It is also the first radio telescope with a controlled-shape surface. In observations at different elevations above the horizon, the shape of its surface varies, remaining in the family of second-order surfaces. The RATAN-600 is also the first aperture-synthesis reflector-type telescope. The location of the radio telescope, its design, its modes of operation, and its future prospects are discussed.<>