GeoGraph - photograph every grid square

Tunnel through "Hilsea Lines Ramparts"

This earthwork, which runs along the Northern edge of Portsea Island, formed the last line of defence from a land attack for Portsmouth. It was originally 2.5 miles long, 9m high and 20m wide. It had six bastions of bombproof casemates and immediately to the North of the ramparts is a moat SU6504 : View from Portsea Bridge, and then a few miles further north is Portsdown Hill, with its series of Palmerston Forts SU6506 : Fort Widley SU6206 : Fort Southwick SU6007 : Fort Nelson.