The French built a large number of batteries around the coast but as the development of armaments progressed and the range of cannon increased, some batteries became surplus to requirements and many were allowed to fall into various states of disrepair and even ruin. Under British rule, some batteries were replaced with Martello Towers, some key batteries were enhanced and some batteries were removed.
Batteries were only originally required in places where large numbers of troops could be landed swiftly and safely. There was no need to site a battery on top of a cliff, where boats could not pass through the reef or where boats could not land safely. This did mean that most batteries were built to protect beaches and have been bulldozed into obscurity in the name of traditional tourism.