The observatory of the Max-Planck-Institut für Radioastronomie, in the Eifel mountains 40 km southwest of Bonn, Germany. It is the site of a 100-m fully steerable dish, opened in 1972, which was the largest fully steerable radio dish until the opening of the 100 × 110-m Green Bank Telescope in 2000. The outer part of the Effelsberg dish was resurfaced in 1998 and a new secondary with active optics was added in 2006. The resurfaced telescope operates at wavelengths from 0.9 m to 3 mm. Effelsberg is also the site of one station of the LOFAR network.
http://www.mpifr-bonn.mpg.de/8964/effelsberg Official observatory website.