This appears to be a false turret to make the fort appear stronger and to act as a diversionary target. Indications that this was a fixed part of the fort are absent.
Its structure and shape indicate that a false turret may have been placed on top of it. Although it was a turret, it was not armed and not connected to the fort via underground.
Again, when the fort was dismantled, the turret must have been sold as scrap metal.
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