About 6 km south of Cattolica, in the hills just over the regional border in Le Marche, the medieval fortress of Gradara is one of the most complete and dramatic small castles in central Italy. Concentric walls, a moat, a thirty-metre keep and a chapel with a Giovanni Bellini polyptych — and a whole tiny walled village tumbling down the hillside outside the inner curtain.
The castle is most associated with the Malatesta family and with the legend of Paolo and Francesca, whose adulterous love and double murder Dante immortalised in the Inferno. It's a 15-minute drive from Cattolica and easily a half-day visit; come early or late to avoid the bus tours.