Does 'It is housed in a Martello A series of such towers, some 12 m (40 ft) high and 2.5 m (8 ft) thick, were constructed along the coast at the beginning of the 19th century to guard against invasion by Napoleon.' exist in a separate context from 'In total, seven towers were built along the coast, and tourists can visit all of them.', without logical interdependence?
It is housed in a Martello A series of such towers, some 12 m (40 ft) high and 2.5 m (8 ft) thick, were constructed along the coast at the beginning of the 19th century to guard against invasion by Napoleon.###In total, seven towers were built along the coast, and tourists can visit all of them.