ThePistoia Mountains Astronomical Observatory (Italian:Osservatorio Astronomico della Montagna Pistoiese;obs. code:104), also known as theSan Marcello Observatory and thePian dei Termini Observatory (Italian:Osservatorio di Pian dei Termini), is anastronomical observatory inSan Marcello Piteglio, Tuscany, central Italy.
The observatory uses a 0.4- and 0.6-meterNewton-Cassegrain telescope and is the home of theGruppo Astrofili Montagna Pistoiese, a group of amateur astronomers known for its membersLuciano Tesi (founder), Paolo Bacci, and the lateVittorio Goretti,Silvano Casulli and Vasco Cecchini.