A continuous rampart, built by the Dutch from mid 17th century onwards and added to by the British, encircles the city, interrupted by 14 massive bastions. The best way to see the fort is to walk the length of the walls (90 minutes), and the best time to do it is during the evenings. Start at the most impressive section, where the Star, Moon and Sun bastions glower forbiddingly over the neck of the peninsula. The ramparts south of the harbour are pierced by the Old Gate, above which is a British Coat of Arms (on the inner side, the gate is crowned by the initials of the Dutch East India Company, VOC, and its coat of arms), and south of the harbour the Zwart (Black) Bastion is believed to be the only surviving part of the original Portuguese fortifications. The circuit of the walls continues via the Akersloot and Aurora bastions to the Point Utrecht bastion, topped by a modern lighthouse, then to Flag Rock, the southernmost point of the walls, before looping back north through the Triton, Neptune, Clippenberg and Aeolus bastions. The final section between the Aeolus and Star bastions is closed, as it is part of a military base. While some of the bastions retain their original Dutch names, the Triton, Aeolus, Neptune and Aurora bastions were renamed by the British in honour of the Royal Navy ships of the line which took part in the British seizure of Sri Lanka from the Dutch during the Napoleonic Wars.