Pistoia Mountains Astronomical Observatory

The Pistoia Mountains Astronomical Observatory (Osservatorio Astronomico della Montagna Pistoiese; obs. code: 104), also known as the San Marcello Observatory and the Pian dei Termini Observatory (Osservatorio di Pian dei Termini), is an astronomical observatory in San Marcello Piteglio, Tuscany, central Italy.

The observatory uses a 0.4- and 0.6-meter Newton-Cassegrain telescope and is the home of the Gruppo Astrofili Montagna Pistoiese, a group of amateur astronomers known for its members Luciano Tesi (founder), Silvano Casulli, Paolo Bacci, Vasco Cecchini and late Vittorio Goretti.