Manx National Heritage has applied for planning permission to remove an extension from the former police station.
The organisation says it wants to carry out work at the former Castletown police station on The Quay to restore it to its former glory.
It was designed by architect Mackay Hugh Baillie Scott in 1895 and was a working police station until 2017.
The iconic Castletown building was bought by Manx National Heritage (MNH) in 2018.
In a planning application, the group said it wants to remove an extension that was built in 1985 and improve the former yard behind it.
Because the building is on the protected register, Manx National Heritage has also applied for registered building consent.
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