It's not free I just paid when i went.
They have certain days that are free. Usually on Thursdays.
It does cost to go. You can pay at the desk.
It's only free if you're a student at UNL, you just show them your ncard. If not, you'll have to pay at the front desk.
I went with a school group during the summer. I didn't set up this field trip so not sure if they had a group discount or school discount.
You can pay at the desk when you go in.
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