Fremantle Harbor Introduction: Fremantle Harbor is the outlet where the Swan River flows into the Indian Ocean. It is known as the best-preserved 19th-century port town in the world. The imprints of early immigrants are everywhere here, which is vividly reflected by the well-preserved Victorian buildings and quaint streets. The Maritime Museum, Fisherman's Wharf and the Fremantle Prison built more than 150 years ago are the characteristic buildings of the town. Walking in Fremantle in the drizzle is the best way to experience this small city.