One of the three gates in the town’s original defensive wall, Castle Gate is the entranceway into the primitive nucleus of Arcidosso and its fortress. The gate’s round archway is built in trachyte ashlars with two protruding moulded shelves, above which there are three coats of arms dating back to the 16th century (the Medici coat of arms in the centre, with two smaller ones either side: one representing the Municipality, the other unidentifiable) and a plaque. In the perimeter wall, there are three arched windows and a finely worked stone 16th century aedicule. Inside the gate, on the right, there is a buffered portal which was probably the gateway to the guard quarters.