The construction of Pembroke Dockyard began in 1814 although a private dockyard already existed at the nearby Milford. The construction of the new Pembroke Dockyard necessitated the building of fortifications around Milford Haven to protect it. These fortifications included:
West Blockhouse, built 1854-7 over 16th Century blockhouse
East Blockhouse, built 1539
Thorn Island Fort, built 1857-9
Dale Fort, 1856-8
Stack Rock Gun Tower, built 1850-2
South Hook
Stack Rock (enlarged)
South Hook
Hubberstone Battery
Popton Point Battery
Chapel Bay Battery
Fort Scoveston (Land Defence)
These fortifications were later supplement by controlled minefields, with submarine mining stations and observations positions. Additional defences were built to illumiate and guard these minefields around Stack Rock.