Torwoodlee Tower plays a part in Galashiels' Braw Lads Gathering.
Work to stabilise the "increasingly precarious" structure started in 2015 and was recently completed.
Galashiels' Braw Lad and Lass for 2017 - Greg Robertson and Amy Thomson - visited the site ahead of celebrations in the town later this month.
A campaign to find the Â£150,000 needed for repairs was launched by James Pringle, the 14th and current Laird of Torwoodlee, some years ago.
The two-year project finally got under way in 2015.
Mr Pringle said: "Torwoodlee Tower has been part of the local landscape for centuries and has a rich and fascinating history."
He said they were grateful for funding from the Fallago Environment Fund, Historic Environment Scotland and members of the Pringle family from across the globe.
Luke Comins, director of the Tweed Forum, which manages the Fallago fund, said it had been happy to support the project "in recognition of the building's significance in the region".
Thomas Knowles, HES head of grants, said: "We're very pleased to have supported the restoration of Torwoodlee Tower to help give a new lease of life to this significant local landmark.
"It is vital that we preserve our historic environment, both for now and for future generations, and I hope that visitors will take this opportunity to come and explore the fascinating history of Torwoodlee Tower."
The completion of repairs to a historic Borders building, which dates back to 1601, has been celebrated ahead of its role in summer celebrations.