No. But parking on top requires state parks permit (discovery pass). $30 annually or $10 for 1-day.
So . . . the "Discover Pass" is a Washington State issued pass, only good at Washington State Parks (and very fee other places but there are a few) OR there's always the day-use fee of $10 that can be paid at the pay station or at any number of manned Ranger/Park Offices at various parks throughout the state. The closest manned Ranger Station to Steptoe Butte however, I believe, is Palouse Falls
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