The Effelsberg 100-m Radio Telescope is a radio telescope in the Ahr Hills in Bad Münstereifel, Germany. For 29 years the Effelsberg Radio Telescope was the largest fully steerable radio telescope on Earth, surpassing the Lovell Telescope in the UK. In 2000, it was surpassed by the Green Bank Observatory's Robert C. Byrd Green Bank Telescope in Green Bank, US, which has a slightly larger elliptical 100 by 110-metre aperture.
The telescope is part of the Event Horizon Telescope, and in part made the first picture of a Supermassive black hole
Wikipedia https://en.wikipedia.org/wiki/Effelsberg_100-m_Radio_Telescope
Address (Unnamed Road), 53902, Germany
Coordinates 50°31'29.394" N 6°53'0.99" E