The tunnels are located along the TransCanada Highway (Hwy #1), a short drive west of Lake Louise, and east of Field, British Columbia (a short distance east of the turn off to Yoho Valley Road that leads to Takakkaw Falls).
When the railroad was first built through the Rockies, they had a really tough time in this area, because the grade was so steep. They were plagued by problems with run-away trains in the early years. How they ultimately solved this dilemma was by building a spiral inside the mountain. There are two of these tunnels, one on the south side of Hwy #1 and the other on the north side.
From the pull out on Hwy #1, you can see the north tunnel. You will actually be able to see the trains going into the tunnel and, after a few minutes, you will also see the front end of the same train coming out of the tunnel, below the bottom end of the train which is still going into the tunnel. You may have to wait up to 40 minutes for a train, but if you are lucky you may see a couple of trains within half an hour.
From Yoho Valley Road that leads to Takakkaw Falls there is a pull out where you can see the second spiral tunnel, on the south side of Hwy #1. It is recommended that you stop first at the pull out along Hwy #1, since there are some photos and stories here about the building of the Spiral Tunnels, as well as a diagram that helps you to visualize how the two tunnels are laid out.
If you look down the hillside immediately below this viewpoint, you might be able to spot the wreckage of a train engine which ran off the old tracks before the construction of the Spiral Tunnels, and has remained there ever since.
In the first photo, look in the center of the picture - under the train engine that is approaching the tunnel. You can see the tunnel exit, and in the third picture you can see the engine coming out of the tunnel below the end section of the train which is still heading into the tunnel.
Most people come to Banff in the summer. The skiers and snowboarders arrive after the hills open - usually in December. That makes November a very quiet off season in the Rocky Mountains and Banff National Park, which is too bad, because you can come across unexpected beauty in this calm season. Note how the Vermilion Lakes in this photo are just beginning to freeze over, resulting in a frosty mirror image of Mt. Rundle.
I have a relative that lives near Banff, so he knew places to go that we would not have visitied without him. If you are not in the best physical shape but you want to see the top of a mountain there are many ways to go about this. You could go up Sulphur Mountain on a Gondola Ride. It was an awesome ride and not too expensive. If you are an adventurous traveller there are trails up the mountain, but it could take you several hours, and you must beware of the animals. If you are someone who thinks they could handle some physical activity the perfect mountain to climb is Tunnel Mountain. It is centered in the middle of the Park, and it is only about a two hour climb. It is all worth it when you get to the top and have amazing views of the Banff Springs hotel.