British home defence and invasion logistics

British preparations included Martello towers, defences around Dover, a military canal and trained militia units. Even Trinity House, the lighthouse authority, raised a militia battalion with William Pitt as its colonel. An invading army could not simply live off the land because Britain's specialised agriculture, industrial resources and population of roughly sixteen million imposed supply and security problems. Southern hills that looked manageable on a map would consume time and energy while offering defenders repeated opportunities for ambush. The invasion problem therefore continued after any successful landing, linking naval transport to a difficult land campaign and supply system.