Penteli Observatory
Penteli Municipality, Greece · built 1958
The Penteli Observatory, also known as the Penteli Astronomical Station, is an astronomical observatory in Penteli, Greece, operated by the National Observatory of Athens. It is best known for housing the historic Newall Refractor, which was the largest refracting telescope in the world when it was built in 1869. From 1959 to 1980 it was a major site for scientific research, though since then it has been facing severe light pollution problems resulting in its gradual conversion into a public observatory, especially after the establishment of the Visitor Center there in 1995. Nowadays, the most notable research conducted in the location is the one carried out by the Athens Digisonde, an ionosonde used for ionospheric sounding.
Observatory data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).