The Pistoia Mountains Astronomical Observatory (obs. code: 104), also known as the San Marcello Observatory and the Pian dei Termini Observatory, 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.

List of discovered minor planets