Between 1804 and 1812 the British authorities built a chain of towers based on the original Mortella tower to defend the south and east coast of England, Ireland, Jersey and Guernsey to guard against possible invasion from France, then under the rule of Napoleon I. A total of 103 Martello towers were built in England, set at regular intervals along the coast from Seaford, Sussex, to Aldeburgh, Suffolk. Most were constructed under the direction of General William Twiss (1745–1827) and a Captain Ford. The northernmost tower at Aldeburgh is of quatrefoil design, i.e. four in one. and there are two towers at Clacton-on-Sea, one near the town and the other to the west near the local Golf Course (see the pictures on the right).