The long-awaited new Shackleton Experience facility, which cost around €2m, is due to open in October.
The project on Emily Square included reconfiguration, refurbishment and extension of the existing, protected three-storey building.
The designs included a two-storey glass and steel extension to the south of building by a specialist designer and sub-contractor.
Internal re-configuration featured the removal of a mezzanine, a lift and two stairways.
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