Johnston Canyon is a popular and stunning hike in Banff National Park, known for its beautiful waterfalls, lush forested trails, and unique elevated walkways. Visitors can enjoy the thrill of walking above Johnston Creek on the canyon walls and getting up close to the powerful Lower Falls in a cave.
I'd recommend hiking at least to the Upper Falls (you'll pass the Lower Falls along the way). This route is about 3.4 miles with 900 feet of elevation gain along an easy trail. Budget about 2 hours for the roundtrip hike.
If you want a longer hike, consider hiking all the way out to the Ink Pots. A unique geological formation that you won't encounter elsewhere in Banff. This involves a 7.5 mile hike with 1,850 feet of elevation gain and will take most visitors 5 hours to complete.
Be sure to arrive early to beat the crowds and to secure parking if you're driving yourself. I typically recommend arriving before 8:00am for this. The waterfalls can become quite congested later in the day.
You can learn more about each of the routes I recommend for this area on AllTrails: