This is from the regulations document you should read about Iowa state parks. That is very important! Off example, but people have been cited for things like not registering kayaks and not wearing safety vests for children while on water, etc. But this part of the document answers your question as pertains to renting a shelter, which is what we did... Only beer with an alcohol content of 5% or less by weight and wine with an alcohol content of 17% or less by weight may be consumed in state parks and recreation areas. Drinking of these beverages is not permitted on roads or in parking areas. Hard liquor and wine with an alcohol content of more than 17% by weight or other alcoholic liquors are not to be consumed in state parks and recreation areas.
No hard liquor
Beer is allowed, as are mixed style drinks (Margaritas and the like), but all alcohol must be in cans no glass bottles allowed. No hard liquor allowed, but you can sneak a flask in if you really want, just leave the shot glasses at home.
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