Mackenzie River
At , the Mackenzie River drainage basin encompasses nearly 20 percent of Canada. About , or 54 percent of the basin, lies above Great Slave Lake. Permafrost underlies about three-quarters of the watershed, reaching up to deep in the Mackenzie Delta. As a whole, the Mackenzie basin receives only meager to moderate rainfall, averaging over the entire basin, though mountain areas experience much higher precipitation, and areas near and north of the Arctic Circle receive much lower precipitation.
Rideau Falls
The Rideau Falls are two waterfalls located in Ottawa, Ontario, Canada, where the Rideau River empties into the Ottawa River. The falls are divided by Green Island, with Ottawa's Old City Hall just to the south. To the west of the falls is the headquarters of the National Research Council while to the east are the Canada and the World Pavilion and the French Embassy. The falls were named by the early French for their resemblance to a curtain, or "rideau" in French. The Rideau River was later named after the falls. The Rideau Canal was constructed to bypass these falls and the Hog's Back Falls.