Situated northwest of Orvieto is the castle of Sala. This is said to be one of the most beautiful medieval fortresses in Italy. The imposing castle was built in the 14th Century by the Monaldeschi, a group of four families that at various times were in control of the nearby towns. The massive round watchtower was a 15th Century addition by order of Angelo Monaldeschi della Vipera, designed as added security. The castle of Sala is in private hands, the home of the marquesses Antinori, but visits can be made by booking ahead.