The square in Castletown re-opened for parking at midday today (Friday).
Commissioners’ chairman Alwyn Collister urged the public to make the most of the parking and its close proximity to shops and support traders by visiting the town.
The square has been closed to traffic since the summer when the regeneration scheme began.
It has deterred the public from visiting the town, causing misery for traders.
They said the disruption had brought the town ‘to its knees’ and in an article in the Examiner said if the public did not support them, there would be nothing left.
Mr Collister said he is delighted with the swift progress made by the contractors, who were originally meant to finish the scheme in February next year.
The authority was also criticised by trader Nic Couchman for cancelling rather than postponing the Christmas lights switch on, which was meant to take place on December 5.
He said the event would have attracted some people into town.
A switch on will be held in the town – but of the civic centre’s new lights – in a carol concert with Castletown Metropolitan Silver Band on Tuesday, December 22, from 7.30pm to 8.30pm