"Cambridge Battery was started in 1862 during the American Civil War (1861-1865) amid heightened Anglo-American tensions, and completed in 1868. Originally called Upper Level Battery or High-Level Battery, it was eventually named for Prince George, 2nd Duke of Cambridge, the Commander-in-Chief of the British Army from 1856 to 1895. Its purpose was to defend the entrance to Halifax Harbour, which British strategists deemed to be essential as a first-rate imperial naval station supporting the Royal Navy. The battery is located on the site of an earlier munitions store that served the Prince of Wales tower and Fort Ogilvie, known as The Old Laboratory. It was designed as an irregular four-faced lunette (a half-moon shaped outwork) with a palisaded gorge (the rear part). At 65-feet above sea level, it commanded a greater height than either of the two shoreline batteries — Point Pleasant and Northwest Arm. The battery’s right face covered the main channel out to sea while the left face fronted across the entrance channel towards McNab’s Island. The short right flank commanded the entrance to the Northwest Arm, with the left flank for self-defence guns against an attack from landward. It is located mid-way between Northwest Arm Battery and the Prince of Wales Tower." -Halifax Military Heritage Preservation Society.