High Quality Content by WIKIPEDIA articles! Cardiff`s town walls were a Medieval defensive wall enclosing much of the present day centre of Cardiff, the capital city of Wales, which included Cardiff Castle. It measured 1280 paces or 1.280 miles (2.060 kilometres) in circumference and had an average thickness of between 6 feet (1.8 metres) and 8 ft (2.4 m) and a height of 10 ft (3.0 m).