You would think with 42 state parks in Colorado, there would be plenty of campsites even for last minute trips. But if you know where and when you're camping, the sooner you book a campsite, the better.

Occupancy varies from state park to state park, with those near major metropolitan areas like Denver filling up first.

Holidays and weekends also are much busier, so if you're camping over the Memorial Day holiday weekend or around Independence Day in July, book now.

Colorado Parks and Wildlife offers both online and phone reservations for Colorado State Parks. They recommend booking sites six months in advance, especially if you are booking a cabin, yurt, or an RV site with water and electricity.

In addition to the camping fee, campers and visitors to Colorado's State Parks must also purchase a parking pass. Those passes are available by the day or an annual pass which is good for 12 months from the date of purchase.

Those looking to find information about camping at a specific park or wanting to explore camping and other activities at any of Colorado's State Parks can view and download the information from the Colorado State Park website.