Starting June 4th, 2020 visitors heading to RMNP will be required to reserve an entrance time prior to entering the park.
Reservations may be made here: https://www.recreation.gov/ticket/facility/300013?q=Rocky%20Mountain%20National%20Park%20Timed%20Entry
Full Press Release from the Staff at Rocky can be read here: https://www.nps.gov/romo/planyourvisit/conditions.htm#covid19
Reservations are needed to access the main entrance, the Adams Falls trail, North Inlet trail and the East Shore trail.
Reservations are NOT required before 6am or after 5pm.
At this time Trail Ridge Road is closed while they clear the ice and snow, but guests may access the first 10 miles of the park (up to the Colorado River Trail)