The Colosseum-like structure, built on a hill overlooking Oban bay, was the dream of philanthropic banker John Stuart McCaig. The tower is nearly one hundred years old, and offers tangible evidence of Oban's fine Victorian past.Statistically, the tower stands approximately 70 metres above sea level, the height of the wall varying from 9 to 14 metres according to the different levels of the ground. The walls are more than 610mm thick with a circumference of approximately 192 metres. It has an entry arch with two windows above it; in the lower tier there are 44 windows whilst there are 50 on top. The tower cost in excess of £5000, a considerable sum of money in Victorian times. The grandiose scheme to keep local stonemasons in work continued until McCaig's death, and although it was never completed, it still serves its original purpose as a fitting monument to the McCaig family.