The ancient castrum of Anghiari is a fortified town that dominates the entire valley. The original nucleus of the town dates back to the 11th century when the Camaldolese monks, supporters of the economic and artistic development of the place, helped to shape the town.
The mighty monastery of St. Bartolomeo, transformed by the Perugians into a defensive building (Cassero) due to its characteristics, is the first building ever to be built in Anghiari together with the Church of the Badia, a place of Christian worship. The walls are almost intact, corresponding to the construction that took place between the 12th and 13th centuries. There are three gates: Sant'Angelo, San Martino and Porta Fiorentina. Characteristic elements of the town are grafted onto the walls : the apse of the Church of Sant'Agostino and the Vicar's Bastion.
The ancient Piazza del Borghetto, now Piazza Mameli, is an obligatory crossroads for those who venture into the alleys of the Borgo.  The two main museums, witnesses of Anghiari’s artistic history  are located right here: Palazzo del Marzocco and Palazzo Taglieschi.

The expansion of the historic center took place in the fourteenth century, when the noble Tarlati family built the long road leading to Sansepolcro and the Loggia with the sources, under the current Piazza del Mercatale, today Piazza Baldaccio, which was in turn enlarged.