The prehistoric hill fort is situated on a rocky spur above the confluence of the Otava and Vltava rivers. The present-day character of the landscape has been completely changed through flooding by the waters from the Orlik dam. Eastern and western slopes of the promontory used to fall steeply some 80m down to the former rivers banks. Northern slope facing the confluence was gentle and subdivided by the terrace platform. This part, and the rest of the spur now covered by castle, were settled in the middle and late Stone Age, in the middle and late Bronze Age and in the Hallstatt and La Tene periods (6th - 1st century B.C.). The ramparts, possibly from late Bronze Age and La Tene periods, were situated next to the northern castle fortification. This part of the hill fort is now submerged. Access to the hill fort was from the south along a narrow isthmus. Another three or four ramparts are situated in the distance of 200-300 m south from the southern castle gate. The origin and date of the ramparts are unclear but it can't be ruled out that they are of Hallstatt age.
