Gatineau Park is a giant wedge of land measuring 140 square miles (363 sq km) to the northwest of Canada's Capital Region. It is a recreational haven for locals and visitors alike, and contains many features of interest. The Luskville Falls are beautiful; the Lusk Cave made of marble can be explored with a hard hat; the King Mountain Trail has 10 observation points and takes an hour to complete; the Mackenzie King Estate, a 231-hectare landscaped space in the heart of the park, was the summer residence of William Lyon Mackenzie King, Canada's 10th prime minister. This green lung is definitely worth a visit on a trip to Ottawa and will easily occupy active visitors for a full day.
Address: 40 Elgin Street