Chelmos Observatory, Astronomical observatory on Mount Chelmos, Greece

Chelmos Observatory stands on the Neraidorachi peak of Mount Chelmos at 2,340 metres, above the Kalavryta ski centre. Its main instrument is the Aristarchos reflector, a 2.3-metre Ritchey-Chrétien telescope built by Carl Zeiss and installed in 2004. The site was chosen for its low light pollution, and the telescope usually sits above the clouds.

Planning began in 1997 under Evangelos Kontizas, then director of the Greek Institute of Astronomy and Astrophysics. Construction started in 2001, with building facilities costing 10 million euros; the Aristarchos telescope, built by Carl Zeiss, was installed in 2004. Power supply and road access were finished in 2007, and the observatory was inaugurated on 20 August 2007.

The telescope is named after Aristarchus of Samos, the ancient astronomer who first proposed the Sun, not the Earth, as the centre of the known universe. The 2.3 m mirror was built by Carl Zeiss AG, and instruments were funded by the universities of Patras and Manchester and the Eugenides Foundation.

The observatory sits on the Neraidorachi peak at 2,340 m, above the Kalavryta ski centre; the final electrical and road access works were finished in 2007. The site was chosen for its very low light pollution, and the telescope usually stands above the clouds. Check opening times before driving up.

The telescope is named after Aristarchus of Samos, the ancient astronomer who first proposed that the Sun, not the Earth, lay at the centre of the known universe. It is the largest telescope in the Balkans and the second largest in continental Europe, with a 2.3 m mirror made by Carl Zeiss.