More Colorado parks will require reservations this summer

What's happening: At least four of the state's most popular outdoor destinations are tightening restrictions this summer. This means visitors can no longer enter parts of Colorado's wilderness on a whim.

• Rocky Mountain National Park's timed-entry reservation permits took effect Monday and run from May 27 through June 30. The park is also upping entry and camping fees and requiring reservations on its Hiker Shuttle for the first time.
• For a second year, Mount Evans Recreation Area is requiring timed-entry reservations, which went on sale Tuesday.
• Reservations will also be necessary at Brainard Lake Recreation Area near Nederland, which go on sale May 26.
• And Eldorado Canyon State Park, south of Boulder, was approved Wednesday for a pilot program that will require vehicle reservations on Saturdays, Sundays and holidays — though an exact start date is not expected until later this summer.