It is reservable.
The sign posted at the shelter says first come, first served. I snapped a picture and shared it on Google Maps. :) Aurora parks website says "20 of the city's parks have reservable shelters with grills. All other shelters are free and first come, first served during park hours." This one is non-reservable. Hope this helps!
Visit the Aurora city website, you can reserve online in most cases.
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