In 1778, Admiral George Rodney took over Pigeon island, expelled the natives, and built a fort on the smaller of the two peaks. This fort is known as Fort Rodney. To establish clear sightlines, Rodney ordered all trees on Pigeon Island to be cut down. From the higher peak, Signal Hill, Rodney was able to observe the French naval base on Martinique.

http://en.wikipedia.org/wiki/Pigeon_Island_%28Saint_Lucia%29