You may want to re-think your impromptu trips to Mount Rainier this summer.

According to Mount Rainier National Park, visitors to Enumclaw’s most-recognized landmark will now need a reservation to enter Paradise via state Route 706 and SR 123 between May 24 and Sept. 2, between the hours of 7 a.m. and 3 p.m.

Reservations are also required to enter sunrise via SR 410 July 3 through Sept. 2 at the same hours.

“In recent years, it’s been too common for visitors to sit in idling cars for a couple of hours at the entrance stations and then make laps through the parking lots hoping for an empty parking space,” said Superintendent Greg Dudgeon in a press release. “We are testing a system that will spread visitation out throughout the day and season to reduce crowding.”

Mount Rainier notes that this is a “pilot” system, which means changes may come in the future.

According to the National Park Service, the number of recreational visitors to Rainier has risen more than 600,000 between 2008 to 2021, from 1.1 million to above 1.6 million. Roughly 70% of those visitors come between July and September, and mostly to Sunrise and Paradise.

This program isn’t meant to limit the overall total number of people that visit Mount Rainier, “but rather spread it out throughout the day and season to reduce crowding,” Chief of Interpretation, Education and Volunteers Terry Wildly continued in the press release.

Before you rush to get your reservation at recreation.gov or by calling 877-444-6777, some reservations will only become available later this winter and spring.

For those who like to plan ahead, you can reserve your Paradise trip between May 24 and June 30 starting Feb. 21. Additionally, July reservations open April 1, and August through September reservations open May 1.

Sunrise visitors can also get their July reservations on April 1, and August and September reservations on May 1.

But for those of you who like to be spontaneous, there will still be next-day reservations available — those are released at 7 p.m. each day through the summer.

Reservations are $2 for one vehicle, and allow for a two-hour entry window. This means someone with a 9 a.m. reservation will be able to enter the park until 11 a.m.

There is no required departure time.

Reservations will only be required between 7 a.m. and 3 p.m.; additionally, those already with lodging or camping reservations for Paradise and Sunrise are not required to get another reservation.

Other permit holders can enter the park without reservations via their wilderness, special use, or research permits, or commercial use authorization.

The number of reservations that are available for each day have not yet been finalized.