The Venetian Castle or Kastelli of Naoussa, Paros is located in the old port of the village and was constructed during the 15th century by the Venetians.
The fortress had a great significance as a watchtower, monitoring the whole bay of Naoussa for pirate and enemy attacks. Today the half-submerged watchtower that survives stands as a magnificent sight and a vigilant guard of the old port.
Facing the Venetian Castle, the small church of Agios Nikolaos, which is the patron saint of sailors and fishermen, is surrounded by colorful fishing boats providing a unique picturesque scenery.