Lake O'Hara is a lake at an elevation of 2,115 m in the alpine area of Yoho National Park, in the province of British Columbia, on the western side of the Great Divide with the province of Alberta and Banff National Park to the east. The lake and the valley are accessible through a bus service that is run by Parks Canada or by an 11 km hike along a road with an elevation gain of approximately 500m. Reservations for the bus can be made up to three months in advance through the Lake O'Hara reservation line. It is strongly recommended that visitors do make reservations as all spots on the bus will book up long in advance.
The area is known for its scenery as well as its alpine hiking. The number of people who access the area by bus has been limited in order to preserve the sensitive alpine environment.
The area is named after Colonel Robert O'Hara, an Irishman from Derryhoyle, Galway who heard about the area from J.J. McArthur, a government surveyor.
The Elizabeth Parker Alpine Club Hut is in the Meadows about a 15-minute walk from the Lodge. It is a ski destination in the winter, with many skiers doing it as a day trip.