Maiden Castle is set just south of Dorchester and can be seen from the main road to Weymouth. The castle itself is no longer visible but it’s location is very obvious to all who visit. Maiden Castle was the largest Iron Age hill fort in Britain and existed as a hill fort between roughly 800 BC and 43 AD when it fell to the Roman army and the local population relocated to the nearby town of Durnovaria, now known as Dorchester.