The Plains of Abraham Martello defence line was composed of four Martello Towers built between 1808 and 1812 under the supervision of Ralph Henry Bruyeres, a Royal Engineer.
The two towers at the end of the defence line were smaller, with a garrison of about a dozen men. The two central Martello Towers were large and had a garrison of about twenty men and three guns could be mounted on the rooftop. The larger towers had wall some 3.5 metres thick on the West (hostile) side, while the East wall facing Quebec was half this thickness. The towers stood at a height of between 8.1 and 10.1 metres (29ft 1-inch to 33ft).
The four Martello Towers had removable cedar shingle roofs that were intended to protect the stone work from the freeze and thaw cycle caused by the weather.
Although intended originally for coast defence, these four towers were primarily intend to defend the land front from an army attack. The Four Martello Towers built: