It once had three layers of massive walls, but the siege of Cesare Borgia in 1497 and subsequent earthquakes have reduced the structures to a state of poor repair.

Trevignano Romano's lakefront promenade, about a mile long and filled with gardens and bistros, is one of the most pleasant places to spend a few hours around Lake Bracciano.

Those who enjoy walking can climb to the top of the stone hill overlooking the historic center, where the remains of the Orsini Fortress, dating back to at least the 13th century, are located.

Trevignano Romano has been awarded the Orange Flag of the Italian Touring Club, relating to its historical-environmental heritage and tourist facilities.

For five consecutive years, Trevignano Romano has also been awarded the Blue Flag, an international recognition that sanctions the quality and cleanliness of the water and shoreline.