GeoGratis is a web portal that allows users to explore and download, without charge, geospatial data and maps of Canada. Search can be done by using geographic names and keywords or by browsing collections. Results can be filtered by geographic coordinates and by type of products (maps, data, publications, etc.)
NOTE: an easy way to identify the geographic area you are interested in along with its National Topographic System (NTS) code is through the Geospatial Data Extraction Tool.
Canada - Additional Geospatial Data
Atlas of Canada
The Atlas offers free small scale data for North America, Canada and Canadian provinces.
Census Geography Files
The Census Boundary Files are the geospatial data files that represent the different census geographies in Canada: Provinces, Census Divisions, Census Subdivisions, Census Tracts, Dissemination Areas, etc. These data are available for the 2001, 2006 and 2011 Censuses. On the same page, you will also find Road network files as well as Correspondence.
LiDAR is a laser-based technology that produces clouds of points providing detailled elevation information that can be used to create a Digital Elevation Model (DEM).
A LiDAR dataset covering the the Island of Montreal is now avaible on the city's open data portal. The data was collected in 2015. The data accuracy (planimetry and altimetry) is 20cm. Note that the files are available in a compressed LAZ format. To use the data in ArcGIS or other GIS software, users need to decompress the LAZ files using a software such as LASzip.
City of Montreal Cartographic Plans (Autocad format)
The City of Montreal detailed cartographic plans, at the scale of 1:1000, contains building footprints, elevation spot heights, and other detailed features. This dataset is available freely on the City of Montreal open data portal.
Transit Data - Societé de Transport de Montréal
The STM transit geospatial data constist of bus stop locations, bus routes, metro stops, metro lines, commuter train stops and lines, in General Transit Feed Specification (GTFS) format. You can download this dataset, from the open data section of the STM webiste.
Development Plan (Plan métropolitain d'aménagement et de développement (PMAD) -- Communauté métropolitaine de Montréal (CMM)
The geospatial data related to the most recent (2012) metropolitan development plan (Plan métropolitain d'aménagement et de développement (PMAD) --as well as the documentation and PDF maps -- are available on the CMM website.