Co Loa Citadel (Thanh Co Loa), 18 km from Hanoi, near the 3rd Highway, is the first fortified citadel recorded in Vietnamese history and dates from the 3rd century BC. Only vestiges of the massive ancient ramparts are extant. Co Loa again became the national capital under Ngo Quyen(reigned 939 to 944). In the centre of the citadel are temples dedicated to King An Duong Vuong (ruled 257 to 208 BC). The present Co Loa consists only 3 circular walls.