I found this just off the trail on my way home.
And, yes, it is occupied.
The Bald-Faced Hornet has a reputation for a severe lack of hospitality; they don't care much for visitors and have no qualms about making their feeling known. On the other hand, they have a sweet-tooth, a fondness for flowers. They are more than willing to inadvertently pollinate your flowers and dispose many of the little critters that like to eat your flowers.