Built in the 1400s (as attested to by a now-lost memorial stone), this gate once had a drawbridge, dismantled in 1780. A moat ran below and, on the side, a tower (which is now part of the surrounding buildings) ensured the proper defence of the southern side of the external walls. The road towards Volterra exited from this point, extending all the way into the territory of the rival Republic of Siena, which probably explains the need for such a well-fortified structure at this gate.