I've got no idea why you all say the pic is placed in the US. From what I can see in this page it is well situated in Banff
Look at Hike #29 in "100 Classic Hikes in Washington" by Manning & Spring. It has better info than any gibberish you'd get from me. It's online on Google Books.
How did you manage to hike to this location? I've wanted to go here but there is no trail and the terrain seems very steep. I think my safest approach may be from the other side; via Slide Lake and Hamar Lake.
That doesn't look like Lake Valhalla.
There's a Big Bend Community College Bonanza right next to it!
In fact it is a silo launcher of ballistic missile R-36orb