The three detached forts at Point Lévy were built to counter the destructive effect of the new rifled canon. If the enemy were to succeed in getting past one of the forts, its troubles were not yet over. Each fort had its own unique system of defence.
Fort No. 1 was designed as an asymmetrical pentagon. While its shape was different from the other two, it nonetheless comprised the same elements of defence.
The ditch was the primary defensive obstacle and skirted around the perimeter of the fort, five metres deep.
Four caponiers were built to defend the ditch and were designed with gun embrasures and loopholes to better aim the artillery. The head caponier covered the fort from side to side. The left and right caponiers covered the area extending from the flanks to the back of the fort. The gorge caponier protected the rear of the forts.
Behind the terreplein was the parade ground. This is where the troops would assemble, where the military exercises were carried out and where sports such as cricket were played.
Buried under the terreplein were 12 casemates housing the barracks for the garrison. Each one could house 12 soldiers. Each man had 15 cubic metres of personal space. This was the new standard for the British army designed to control promiscuity and prevent epidemics.
For obvious security reasons, the powder magazine was located at a fair distance from the casemates. It had to be readily accessible but well hidden under the terreplein to prevent any accidental explosions. An excellent example of a bombproof magazine!