The complex includes: the Museum of the City and the Territory, the Pinacoteca, the Antiquarium, the Church of San Francesco, the Museum of the Olive Tree Civilization.

The rooms of the Museum of the City and of the Territory preserve evidence from the Roman era to the nineteenth century. The archaeological section exhibits excavated materials (stones, inscriptions, terracotta) coming mainly from the Pietrarossa locality, site of the ancient Roman Trebiae.

The Pinacoteca houses works of extraordinary historical and artistic interest from the medieval and Renaissance period: triptych and quadriptych with the Stories of the life of Christ by Giovanni di Corraduccio, the Coronation of the Virgin by Giovanni di Pietro, known as Spain, a Madonna and Child from the early period of Pinturicchio and the large altarpiece with the Assumption of the Virgin and saints by Alessandro Turchi known as l'Orbetto.

The architectural typology of the Church of San Francesco is very simple, according to the style of the mendicant orders: a single nave with a wooden truss roof, with a pentagonal central apse flanked by two rectangular chapels. The apse has frescoes from the first half of the 14th century on the walls, depicting the Stories of the Life of the Madonna. In the center of the apse there is an iconostasis cross from the early fourteenth century.

Trevi could not miss a museum dedicated to the cultivation of the olive tree and the production of oil in the Trevi environment and in the Mediterranean environment. The visit itinerary opens with the story of a local farmer who, even with the help of dialectal expressions, accompanies the cycle of olive cultivation, production and conservation of oil, with indications on techniques processing and extraction, rituals, superstitions and typically local religious beliefs. The itinerary continues in four didactic sections: botany; we know the oil and the olive tree; the olive tree symbol of peace; history of the olive tree.