Today the tunnel system remains Ministry of Defence property and they are used to train troops for subterranean work. Guided tours can be arranged to view the remains of the World War II installations such as the kitchens, Nissen huts, the abandoned generating station and anti-submarine nets which would have been used to close off Gibraltar Harbour to protect the Allied ships berthed there. The approximately two-hour tour normally starts at Maida Vale, at an entrance behind the old casino on Europa Road, and proceeds through several large chambers visiting Brigade Headquarters and continues for almost arriving at the Calpe Hole Generating Station.