This incredible offshore fortress and defense gun tower at Pembroke Dock, South West Wales, UK is for sale.
It was built in 1851 and "designed to be operated by one officer and 33 men." Offers above £70,000 will be entertained. From the real estate listing:
The North East Dockyard Tower was originally built to accommodate officers and men with storage for powder and provisions. The roof had guns mounted on traversing platforms and 12-pound brass howitzers in order to defend the Royal Dockyard of Pembroke Dock. The building is three stories in height and as you would expect solid in construction, however, it requires maintenance. Being offshore, the tower offers sweeping views of the Cleddau River, Pembroke Dock, Neyland and Llanstadwell.