For what seems like years, people who were looking for freely accessible Canadian data could only look enviously at their neighbours to the south and wonder why Canada could not follow the Americans lead in the free distribution of large scale base data. That is beginning to change. With some provinces making some of their base data available and the federal government's latest GeoBase offerings, Canadian, large scale data is becoming more accessible. It still has a ways to go to being as extensive and complete as the American data holdings available through USGS but it's getting better.

This is meant to be a short listing of freely available Canadian base data. There are many thematic datasets out on the web - a quick look at the GeoConnections page would show that - the focus of this article is base data, that is, road and transportation networks, drainage, elevation data, named points, and administrative boundaries. There are also many international datasets, usually at smaller scales, such as the Digital Chart of the World that include Canada but these are not included (with one exception). If I've missed other Canadian base data sources contact me and I will include them in future lists.

GeoBase
The newest kid on the "free data" block. The current data holdings here are relatively slim and spotty but the data that does exist is well worth the visit: Landsat 7 ortho-rectified imagery (also available from Geogratis), 1:50,000 and 1:250,000 digital elevation models, National Road Network (available for 4 provinces and all 3 territories), geographic names and various geodetic control points. Select a dataset, enter your email address and wait for an email to arrive indicating that your request is ready to be downloaded. The site has promise and should be visited regularly for updates.

Geogratis
Perhaps not as new or flashy as GeoBase but still one of the best sites to visit for Canada-wide, freely accessible data. Base data is available at 1:1,000,000 for the entire country but there is a host of other more thematic data freely available, including the Canada Land Inventory at 1:50,000 and 1:250,000, Landsat 7 data (straight download here without having to fill out any forms; you just need to know the scene you're looking for), electoral and census boundaries, and GTOPO30 digital elevation data. There are also a number of great national datasets at smaller scales of 1:2,000,000 to 1:75,000,000.

Toporama
Looking for that NTS sheet you don't have? Visit the Toporama site. Simplified raster versions of both 1:50,000 and 1:250,000 NTS sheets in geographic format are available for download and use as well as Landsat ortho-imagery.

Canada 3D
Two national digital elevation models available in ASCII grid format. One has a 300 arc-second resolution, the other has a 30 arc-second resolution. Both are in geographic format. Similar digital elevation data at 30 arc-seconds is available from GTOPO30.

Shuttle Radar Topography Mission
A few years ago one of the Space Shuttle's missions was to map 90% of the earth's land surface between 60°N and 60°S (Sorry, Territories! But for the Yukon see below.) using radar technology. The result is 30 m digital elevation models available in 1° tiles. The format is hgt. The quickest and best way to view it is using a free program called 3Dem.

Yukon Department of Renewable Resources
Most of the data that the Yukon seems to use is NTS data and, as a result, they are unable to share it freely. Data that is available includes 30 m and 90 m digital elevation models, territorial boundary, and parks and protected areas, among others.

British Columbia Ministry of Sustainable Resource Management
There are a number of data layers for BC available here, including park boundaries and a hillshade image. Scroll down to the bottom and there is a listing of districts. Select any of the districts to open up a listing of larger scale data. The problem is, there doesn't seem to be any clear indication as to what is what. Some guesswork as to what is what may be required.

Manitoba Land Initiative
You'll need to register to access the data which includes a collection of base datasets ranging from 1:20,000 to 1:2,000,000 as well as dems for the Red River Valley and southern Manitoba. There is also land use, soil classification, forest inventory and other data available.

GeoConnections
A good place to start your search for free data in the country. Most of the data listed here is thematic and very specialized but it's worth a look.