In looking at Garmin Pilot, there is something labeled "Vancouver FIR" which has 3 segments. It's located over the northern Cascades and to the east of the northern tip of Vancouver Island (Canada). What is that "Vancouver FIR"?
Specifically, I'm interested in flying over those mountains at a few thousand feet AGL (in and among the mountains) and am wondering if this "Vancouver FIR" is something I need to worry about.
I'm currently working on obtaining my Private Pilot Certificate in the United States.