My local trailhead a few miles east...
It does make me feel warm and fuzzy to pay fees that pay someone to see if I paid my fees.
I understand it the same way. If I just pull off a dirt road I do not need it, but if there are any improvements, (trailhead, restroom, picnic area, etc) then I do.
I have only used the interagency pass at gates or booths that were staffed. Wondering if anyone can confirm it works like the adventure pass- can I leave it on the dashboard and walk off?
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Oh got it - I need a hang tag
http://www.fs.fed.us/passespermits/annual.shtml although it looks like it comes with the pass, the park ranger I bought it from never mentioned or offered a hang tag. Guess I gotta get them to send me one.