Charming Montreal is actually two cities in one: There’s the city everyone knows with its Old World accents, and then there’s the underground city known as RESO. This 1.5-hour guided tour explores the city's popular above-ground sites and the subterranean city where 500,000 people circulate daily among 2,000 shops, hotels, bars and restaurants. Learn about the engineering behind this underworld as you explore the various nooks below one of Canada’s most dynamic cities.