The Val di Merse stretches across an enchanting landscape, in which squares and towers, villas and castles predominate, with the City of the Palio in the background. It owes its name to the fact that it is crossed by the River Merse.

The area is almost entirely a nature reserve characterised by extensive woods of holm oaks, chestnut trees and broom and furrowed by small streams. It is home to numerous species of animals that are now rare. The area is rich in medieval villages that have preserved their magical original appearance.