The ruined medieval watchtower standing in the sea just north of Ladispoli is the town's most distinctive landmark. Built in the 16th century as part of a coastal defense network against Saracen raids, Torre Flavia now stands isolated on a rocky shoal, reachable only by wading or at very low tide.
The surrounding area is a wetland nature reserve managed by the WWF — a good spot for birdwatching, particularly for migratory waders in autumn. The coastal path from Ladispoli's northern beach stretches about 2 kilometres to reach the tower.