The pair of towers on Sherbrooke street are among the oldest structures in the city, according to the Centre d’histoire de Montréal. However, sources conflict as to whether they date from the construction of Fort de la Montagne in 1685, or whether they were erected when the wooden fortress was rebuilt out of stone after a fire in 1694.
Fort de la Montagne originally housed a Sulpician mission to convert and school Native Americans. In 1685, 210 people of the Iroquois, Huron and Algonquin Nations inhabited the site. Marguerite Bourgeois and the sisters of the Notre-Dame congregation used the south-west tower (below) as a school and the south-east tower (above) as a residence.
The pair of northern towers were demolished in 1854 for the construction of the Grand Séminaire.