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Following the Trail of Montréal, the 18th-Century Fortified City

Discovery Tour of Old Montréal’s
Archaeological Sites
Gaspard-Joseph Chaussegros de Léry, born in Toulon in 1682, was the King’s chief engineer in New France from 1716 to 1756. During this time, he planned and supervised work on several defense systems in Montréal, Québec City, Fort Chambly, Fort Niagara, Fort Saint-Frédéric and Sault-Saint-Louis (Kahnawake). Today, the spirit of Chaussegros de Léry beckons us to discover these historic places by following these marks on the ground, the archaeological reminders of a bygone era.


Did You Know
That Montréal
Was a Fortified



 Chaussegros de Léry 

Chaussegros de Léry

When it was first founded,Montréal was defended by fortified structures. As early as 1688, the colonial administration urged its inhabitants to build a large number of small forts,houses, fortified mills and redoubts—outworks or fieldworks without flanking defences.The first stockade,made of wood,was erected between 1687 and 1689. Louis XIV gave his consent to build a stone fortification in 1712, and construction began in 1716.

The new stone ramparts, built between 1717 and 1738, were a symbol of authority and a guarantee of security, which both had a positive impact on the economy of Montréal. In 1744, as war loomed, improvements were made. The ramparts were designed according to the rules of fortification, the construction art that takes the topography of the site into account. Since Montréal is situated on relatively flat land, it was easy to apply the principle of flanking, which requires that all parts of the fortified wall be in the defenders’ full view.This strategy was intended to protect the city from the greatest threat to its security: a standard siege from a large military troop pulling small artillery.

 Map of the City of Montréal, September 10, 1725 by Chaussegros de Léry. Archives nationales (France), no 475B
 Map of the City of Montréal, 1725
Three Types of Ramparts

The perimeter of the stone ramparts totalled approximately 3,500 metres, and like the stockade that preceded them, the new ramparts consisted of strongholds and curtain walls forming 14 defensive fronts. The main wall, or enceinte, was roughly six metres high and included eight large doors—some with drawbridges—and eight posterns, or side entrances. The structures were constructed from grey crystalline and black limestone stonemasonry and all the rampart walls—consisting of three distinct types of ramparts forming an irregular-shaped enclosure—were coated with roughcast, a plaster made from lime and sand.

 Three Types of Ramparts
  A   Scarp
  B   Supporting Wall
  C   Terreplein
  D   Ditch
  E   Counterscarp
  F   Glacis
Tools used for stonework
Tools used for stonework. Anonymous,
circa 1740. Archives nationales du Québec

A stonemasonry wall was built on the side facing the St-Laurent River, where only attacks by boat were possible. This wall was mounted with a parapet, pierced with meurtrières, or gun sites, and, in some places, was reinforced by a supporting wall and a terreplein, or sloping bank.

A wall similar to the one facing the St-Laurent was built on the land side to protect the enclosure from small cannon fire.This wall was reinforced with a banquette—a step running along the inside of the parapet and supporting the wall-walk. A ditch and a glacis, or forward slope,were also planned and together, they formed a defensive barrier over 25 metres wide.

Many types of craftsmen were recruited: the most important were stonemasons and stonefitters, but haulers, carpenters, blacksmiths, sawyers, locksmiths, roofers and other craftsmen also lent their specialized skills to the site. However,most of the workers were labourers, hired by building contractors and construction supervisors to work alongside soldiers.

The 18th-century fortified city formed a dense urban mosaic, dotted with large buildings—many belonging to religious communities—landscaped with great walled gardens, and nearly 400 houses were built during this time of expansion. The fortifications were gradually dismantled between 1804 and 1817 following the adoption of The Act to Demolish the Old Walls and Fortifications Surrounding the City of Montréal in 1801.

Free from its enclosure walls, the city and its suburbs now opened directly onto the river. This soon changed the very pattern of the city, and as early as 1805, twice as many people were living in the suburbs as in the city.

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