The first mention of Montelpio dates back to 1356 in an ecclesiastical deed where reference is made to a church with a shelter, also known as a ‘mansion’, used as a dwelling by the Knights Templar (or Knights of Rhodes).
In the village stood the parish church of San Martino, an important parish church, demolished at the behest of a local marquis who, legend has it, was later run over by his own horse as punishment for having it demolished. The Chapel of San Domenico was built in its place. The village was home to noble families such as Frescobaldi and Gaetani, who appreciated the area rich in woods, vineyards and olive groves.
A number of historical buildings can still be seen today, including Villa Mazzetti, built in the 19th century on top of a structure dating back to 1248, which still bears the Gaetani coat of arms and still retains the typical features of ancient Templar residences. Over the centuries, the villa has had various owners but has retained its original structure with terracotta floors and ceilings with exposed wooden beams. Adjacent to the villa is a large garden that can be accessed by the staircase descending from the main floor.
On the municipal road of Montelopio is Villa Ballati Neri, a 13th-14th century manor house formed by the aggregation of pre-existing buildings forming two courtyards, one at the front and the other at the back.