Nope, it is free to visit during its hours of operation! The local guides are super helpful and can provide you with free pamphlets to make your hike more educational. (They do sell some non-alcoholic "birch beer" as a way to help raise funds, so it doesn't hurt to support them in that way!)
+1 to Lucas' answer. Plus the birch beer is a natural recipe with birch oils and cane sugar. Yum!
Nope, it's free but you can make a donation.
Thanks for your help.
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