The page at the following link details all of your options: https://www.longmontcolorado.gov/departments/departments-n-z/recreation-services/facility-information-recreation/recreation-facility-fees
One fee for daily entrance, includes any activity. Same fee for swimming, exercise equipment, gym access, or all of the above.
It is under 10 dollars for a day pass. I can very in price for there memberships. I hope this is somewhat helpful. It depends on what you want to do.
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