The Denver Zoo is pretty easy to get to from almost anywhere in the area, and it's become one of our favorite places. Our 4-year-old loves going to the zoo! Boo at the Zoo in October, usually just before Halloween, has been a big hit. If you've got a big car/SUV, heads up (so to speak) on the parking garage; you might be better off parking on the roof or in the other lots.
The only drawback to the whole experience is some mighty expensive food and drink choices, but there's plenty of picnic benches and bringing food is just fine.
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