Another Canadian entry on our list is Montreal. Known for its charming Old Town and francophone population, this city in Quebec Province has a unique way to help people stay out of the cold: the Underground City. Stretching for more than 20 miles through the five-square-mile core of the city, its subterranean climate-controlled walkways and retail spaces connect to most of downtown's main buildings and the city's far-reaching subway network. Theoretically, the more than 500,000 people who use the Underground every day could get to almost any attraction in the core of Montreal without having to step outside.
Another indoor attraction is Montreal's Biodome (pictured), a huge indoor botanical garden/zoo can give visitors a taste of the tropics, even at the height of the chilly and snowy Quebec winter. That said, with ice skating rinks, wintertime festivals and the charming streets of Old Montreal, visitors will still want to pack wintertime clothing.