Ripley's Aquarium of Canada sits at the base of the CN Tower and has been one of Toronto's most popular family attractions since opening in 2013. The main highlight is the Dangerous Lagoon — a 97-metre walk-through underwater tunnel where sharks, sawfish, and green sea turtles swim overhead and on both sides. A moving walkway carries you through slowly enough to watch the animals in detail.
The aquarium holds roughly 20,000 aquatic animals across 5.7 million litres of water. The Canadian Waters gallery covers freshwater species from across the country; the Rainbow Reef section has a vivid collection of tropical reef fish. The jellyfish gallery is particularly good, with species displayed against coloured backlighting.
Tickets should be booked online in advance; the aquarium gets extremely crowded on weekends and during school holidays. It is open until 11pm on Fridays and Saturdays, which is a better time to visit — quieter and more atmospheric than daytime.