This photograph of Horsea Island in the north-eastern corner of Portsmouth Harbour is undated and I’m hoping readers can come up with the answer.
It comes from Commander Bob White of HMS Collingwood at Fareham, who is interested in the island’s history.
We’re looking south-east towards Tipner, Alexandra Park, and the spot that is now home to the Mountbatten Centre in Portsmouth. The dominant feature is the navy’s 1,000-yard torpedo testing lake.
One clue to its date might be the large masts which formed part of the navy’s wireless station. I could spot 23, but there might well have been more. It closed in the 1960s.
Of course, Horsea at this time was a true island when access was only possible by boat.
Compare it to the 1973 photograph here when construction of the M275 and M27 was in progress.
Now you can see just how much reclamation of the harbour that project entailed. It would pave the way for Port Solent and meant Horsea Island lost its island status.
Cdr White’s picture was taken at low tide and on the left there appears to be a mysterious old track.
There are suggestions that it might be the remains of an ancient causeway used by boatbuilders at Portchester in Tudor times when the sea level was lower.
Horsea was originally two islands, Great and Little Horsea, the former large enough to support a dairy farm.
The islands were joined to form the torpedo testing lake in 1889, using chalk excavated from Portsdown Hill by convict labour.
A narrow-gauge railway was built on the site by the army to distribute the chalk.
Although the lake’s length was increased from 800 yards (730 m) to more than 1,000 yards (910 m) in 1905, rapid advances in torpedo design and range had made it all but obsolete by the First World War.
In the 1950s the lake was used to test the improved Martin Baker ejection seats, following catapult launch mishaps on carriers in which Fleet Air Arm aircrew often suffered serious compression injuries to the spine after ejecting from submerged aircraft.