"Mt. St. Helens and Yale Lake"
Appears to be from the 1960s. This is an artificial lake created by a dam in the early 1950s. It is also the area where skyjacker
D.B. Cooper was thought to have landed, mostly in neighboring Lake Merwin.
St. Helens, of course, no longer looks like that. The 1980 eruption literally blew the top off.