"The Rideau Canal in Ottawa, Canada freezes over each year to form the world's largest natural ice rink, stretching 4.8 miles from Downtown Ontario to Dow's Lake. Access is free, offering over six square miles of frozen canal for skating. The rink features rest areas with fire pits, changing rooms, and vendors selling pastries. It typically opens in January and runs until late February, requiring 12 inches of ice thickness to support the daily 20,000 skaters. The canal also hosts Winterlude, a winter celebration with various ice-related activities."