A reservation system is now in place for anyone wanting to drive into Yosemite National Park at peak times during the park’s busy season.

Between May 20 and Sept. 30, peak-hours reservations are required between 6 a.m. and 4 p.m. every day as part of efforts to ensure the park does not get overfull.

“What we’re trying to do is basically preserve the quality of the visit,” said Yosemite National Park’s Scott Gediman.

Only one day-use reservation is needed per vehicle and it must be purchased in advance (they are not available at the park entrance). The National Park Service states that each reservation is good for three consecutive days beginning with the day of arrival initially reserved.

Gediman says the aim is not to limit visitors – but instead spread them out.

“What was happening before was we got so many people coming in. We get to 10 or 11 o’clock and you get two-hour waits at the entrance station – parking lots are full, trails are full.”

A reservation is not required to enter Yosemite National Park if you have a space booked on a campground, have organized a vacation rental, or have paid to take part in a class inside the park (such as a guided backpacking trip) – although a visitor will be asked to prove it when they arrive at the park entrance.

A reservation is also not needed if you are entering the park on the YARTS bus service.

“Think of it this way: if you already have a reservation, whether it’s on a YARTS bus or a hotel or campground, then you’re good. Just the day users,” said Gediman.

Those planning to arrive before 6 a.m. or after 4 p.m. are asked not to block the roads in front of the park entrance station but instead alter their journey so that they arrive at the intended time.

“It’s not to limit the visitation, it’s to flatten it out,” said Gediman. “Which will hopefully either eliminate or reduce lines at entrance stations, full parking lots, full shuttle buses, crowds on trails – which ultimately is better resource prevention and a better experience for the visitor.”

Reservations can be purchased for $2 at recreation.gov. Park officials say 70% of the reservations were released for sale in March, but the remaining 30% is on a rolling release schedule, seven days ahead of the reservation date itself, for those who want to be a little bit more spontaneous.