South of Rønde is this popular feature of Mols Bjerge National Park. From the parking area and restaurant, a 500m causeway leads to atmospheric castle ruins sitting atop a small island in an inlet of Kalø Bay. The ruins were built by Danish king Erik Menved in 1313.
In the Kalø area are typical park features like forest paths and bird-filled beach meadows. A new park visitor centre is planned for the site.