Historic England has awarded £118,000 to help repair a crumbling coastal fort in Clacton.
Martello towers were forts built in the early 19th century to protect the coast from invasion during the Napoleonic era.
Many of the 29 which were constructed have been lost and most of the remaining ones are either private homes or stand derelict.
Tower E, which sits towards the western end of the Clacton shore has long been deemed in a poor state of repair.
But now the Historic England money will help with roof, floor and render repairs to the Grade II listed scheduled monument.
The tower stands at a height of 10 metres, with up to 4 metre thick walls facing the sea and is sloped inwards to resist cannon fire.
The open top floor, supported by a vast central pillar, carried three guns set on swiveling carriages.
The middle floor formed living quarters for about 25 men and contained the only external door in the tower, some 3-4 metres above ground level.
The semi-basement ground floor contained the powder magazine, alcoves for shot, cartridge and general stores and a water cistern.
Despite some 20th century alterations, the structure remains substantially intact and is known to retain original details dating from the period of construction.
The openings, four windows, door and the ladder chute below it have all been sealed in recent years to prevent vandalism.