The Lewis War Memorial is undergoing a major £230,000 restoration.
Stonework repairs and internal works aim to stop leaks and prevent the building from further decay.
Because of its prominent unsheltered spot on the top of Cnoc-nan-uan, the building has suffered damage to its stonework over the years.
The latest stage of the repairs is due to begin this month, with Architectural Conservation of West Lothian winning the contract for the specialist work against three other bids.
The memorial was built in 1924 but access into the tower stopped in 1975 on safety grounds following the deterioation of the internal staircase and walls.
Bronze plaques bearing the names of islanders who lost their lives in conflict were removed from inside the tower and mounted on granite stones outside in 2002.
The external works primarily consist of stonework pointing, stone replacement where necessary, replacement of 15 slim windows with new louvres and refurbishment of four windows on the fourth floor.
Restoration works will be undertaken to the three bartisans and the turret steps, entrance door ceiling and slit windows will all be refurbished.
Internal work will involve the removal of existing secondary material – cement render, plaster and paint – to expose the inner rubble stone surfaces to walls.
The restoration is being led by the comhairle, which is funding £100,000 towards the overall project. The War Memorial Trusts World War 1 Memorials Programme awarded the works a £132,000 grant.
A council spokesman said the work would take several months but should be finished by November when the annual Remembrance Sunday service was held at the memorial.