Nab Tower Lighthouse

Nab Tower Lighthouse was built in 1918 as part of a series of unfinished First World War defences, and then used from 1920 to replace the Nab Lightvessel

This light is responsible for guiding ships of all sizes and nationalities into the deep water channel for Portsmouth and Southampton.


In the early part of 1918 attacks by U-boats on the UK’s merchant fleet caused the Admiralty so much anxiety that it was decided to take strong, if unorthodox, counter measures and a startling plan was drawn up to sink a line of eight fort-like towers (each costing £1 million) across the straits and to link them with steel boom nets, with the idea of closing the English Channel to enemy ships.

About 3,000 civilian workmen were brought to a quiet backwater at Shoreham and work began almost at once on two of these towers: each 40 feet in diameter with latticed steel work surrounding the 90 foot cylindrical steel tower and built on a hollow 80 foot thick concrete base designed to be flooded and sunk in about 20 fathoms. The vast honeycombed concrete base was shaped with pointed bows and stern for easy towing.

One tower was completed when the war finished in November, and the other half-finished giant was broken up for scrap. After much thought it was decided to use the solitary ‘white elephant’ to replace the Nab Lightvessel by sinking it at the eastern end of the Spithead approaches, also serving as an invaluable naval defence post if required.

On a calm day in 1920 two paddlewheel tugs towed the tower to a position near the lightvessel. There were many anxious moments as the base was opened to the sea, but this brain child of civilian designer Mr. G Menzies settled without incident, kept steady by the immense volume of water inside the base.


Staffed from 1920 to 1983 as an offshore lighthouse, by three lighthouse keepers who were relieved monthly, the station was automated in 1983 and converted to solar powered operation in 1995.


In 2015 the ageing and corroding structure was re-engineered; the height of the tower was reduced significantly, the metal outer framework was removed and a new 12 mile light was installed.

The lighthouse is now monitored and controlled from Trinity House’s Planning Centre in Harwich, Essex.