oooh btw I went to Vancouver and Seattle this summer, visited the Boeing factory and went plane spotting at SEA and YVR. At YVR apparently there's this park right behind the runway and it's awesome for planespotting! At SEA I used the cell phone lot
If you mean flight path park it's terrible. If you mean Terra Nova it's good, but you need a really long lens which I don't have lol. At SEA I like the Water Tower and down the hill from Mathison park. Water tower in the morning, Mathison in the afternoon. Then Angle Lake station in the morning for arrivals on the other end, and 188th street in the afternoon. At YVR, I like Templeton Station if arrivals are coming in on 26R, since it's double-sided so it never gets backlit. For departures the south terminal viewing platform is AMAZING