Brock Canada‚Äôs scaffolding surrounds Saint John’s Carleton Martello Tower National Historic Site as part of the rehabilitation of the over 200-year-old stone structure. The Carleton Martello Tower is a designated national historic site that draws considerable tourism, but the structure has seen better days. Parks Canada says investigative work in 2015 showed the tower was in a state of ‘critical failure.’ Brock is proud to be part of the team making this historic structure safer for everyone to enjoy.