The Calar Alto Observatory is located in the Sierra de Los Filabres Andalucía Mountains in Southern Spain, north of Almeria. It is jointly operated by the Max-Planck-Institut für Astronomie in Heidelberg (Germany) and by the Instituto de Astrofísica de Andalucía-CSIC in Granada (Spain). It provides three telescopes with apertures of 1.23 m, 2.2 m, and 3.5 m as well as a Schmidt reflector. WEBT observations at the Calar Alto Observatory are done under the MAPCAT program coordinated from the Instituto de Astrofísica de Andalucía-CSIC.
Telescope parameters: Long= -2.54625 deg, Lat= +37.2236 deg, Alt= 2168m.