According to ComScore in November 2010, the top 10 web properties in Canada (in order) were: MSN, Google, Facebook, Yahoo, Wikimedia Foundation, eBay, Ask Network, Sympatico, Apple and Yellow Pages Group.
Out of this group 9 of these properties existed back in 2001. Facebook was the only one that did not exist, so for Facebook, we go back to 2006.
Here is the visual of Canada’s Top 10 Web Properties from 10-years ago:
Facebook – Note 2006 is the first image
Finally, some very popular Canadian websites that are due an honorable mention:
The Weather Network
Images are screencaps taken from WayBack Machine.