From the source:
Built in 1927 for the Canadian Pacific Railway, the Plain of Six Glaciers Tea House is one of the most historic and famous buildings in the Canadian Rockies. With panoramic views of the 6 glaciers, the tea house offers a truly delicious lunch or snack cooked in a traditional way without electricity. Home baking at its best! Be prepared to receive a warm welcome to this special place, which has been owned and run by the same family for 60 years! Take the Plain of the Six Glaciers Trail around the shoreline of Lake Louise, follow it into a narrow valley that leads toward Mount Lefroy and Mount Victoria. The Plain of Six Glaciers Tea House is approximately a 5.5 km hike from the shores of Lake Louise.

It does have seasonal closures, so make sure to check ahead of time!!