Linn Cove Viaduct is a 1243-foot concrete segmental bridge which snakes around the slopes of Grandfather Mountain in North Carolina. It was completed in 1983 at a cost of $10 million and was the last section of the Blue Ridge Parkway to be finished. It is said to be the most complicated concrete bridge ever built.   It consists of 153 segments weighing 50 tons each. It is claimed to be the most complicated concrete bridge ever built.