Falmouth is the most south westerly deep water harbour on the English Mainland and was therefore important for urgent communications with the Americas. The Falmouth Packet Service was established in 1688 and used light but fast sailing ships to take passengers and Royal Mail to and from the expanding British Empire. Until 1850, with the introduction of steam power, Falmouth was second only to London for the Packet Service. It functioned as a communication hub for the early British Empire, with over thirty Consulates in the town. With the introduction of extensive cable communications, Porthcurno, only 38 miles from Falmouth, became the landing point for many of these cables.
Falmouth Harbour on the south west coast has been fortified since the Iron Age. The first artillery fortifications were St Mawes and Pendennis Castles built by Henry VII were completed by 1545. Over the next centuries fortifications were built at Pendennis Head, around St Mawes and also St Anthony Head.
Building of a new battery at Pendennis Point was stopped in 1846 but in 1852 both Pendennis and St Mawes batteries were re-armed with new artillery.
By 1865 docks had been built at Falmouth. In 1889 a submarine mine field was deployed to cover the harbour, complete with Observation Posts, defence electric lights and quick fire gun batteries.
In 1895 6-inch BL guns on HP mounting were built at Pendennis at St Anthony Head.
In 1901 new barracks were built at Pendennis, and by 1902 a regiment of artillery was in residence.