The best thing to do is read the signs because its different in each area, but its beautiful and well worth any fees.
The flume is more than $5. I know a discount combo pass for the flume and the airal tram is like $30. The flume alone is $16 or so. It is a beautiful walk, but most of the proper hiking trails like the Appalacian in Franconia Notch State Park and the greater White Mountain National Forest are free.
Flume gorge costs $5 but mostly are free in that area. Well worth the fee, it helps to maintain the trails and all its beauty.
Some trails have fees and some are free
Some trails have a fee.
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