It’s mud season in New England, which means many trails are temporarily closed and campgrounds aren’t yet open.

Still, visitors can use this time to plan their adventures in Maine’s state and national parks, which will see some changes — such as higher fees and new facilities.

Here’s a primer on what’s new and important to know about the parks this year.

HIGHER FEES, BUS SERVICE AT ACADIA

The biggest change at Acadia National Park this year is for foreign tourists.

An America The Beautiful Pass, which covers entrance fees at many national parks and federal lands, jumped to $250 for non-U.S. residents in 2026. The pass will still cost $80 for U.S. citizens and residents.

Foreign visitors who do not have that pass will need to pay an extra $100 per person on top of the standard entrance fee to get into the 11 busiest national parks, including Acadia. Current daily entrance fees for Acadia range from $20 to $35.

Last year, Acadia recorded 4,042,403 visits through the end of October, an increase of 3.2% over the same period in 2024, according to park service data. August was the busiest month since 1989.

Campgrounds, park roads and facilities open gradually throughout April and May. Carriage roads are only open to pedestrians during mud season, and several hiking trails are closed in spring to protect nesting peregrine falcons. The majority of the Park Loop Road is already open to visitors, but the Cadillac Summit Road is closed to all uses through April 30 to accommodate construction on a connector trail, according to the park.

Check the park website for information about park closures and operating hours.

The new Acadia Gateway Center in Trenton opened last fall, and visitors will be able to leave their cars at the park-and-ride. The free Island Explorer bus will start spring service May 20 between the gateway center and the Village Green in Bar Harbor and on the Park Loop Road.

Paul Murphy, executive director of Downeast Transportation, which runs the Island Explorer service, encouraged visitors to take advantage of the bus and plan ahead during the busy summer months.

“Parking is very competitive at Acadia National Park,” Murphy said. “Finding a space can be difficult. Driving around the park can be difficult. We have bus service that can get them to most places in and around the park and Mount Desert Island. That’s advice they will be happy to have taken.”

Full summer service will begin June 23. Visit the Island Explorer website for routes and timetables.

CAMPING AT THE PARKS

Visitors can make reservations for camping within Acadia National Park online at recreation.gov. Reservations cannot be made at the campground office or in person, according to the park. Most campsites open six months in advance on the first day of the month at 10 a.m. Sites for Duck Harbor Campground on Isle au Haut opened for the entire season on April 1.

Baxter State Park introduced a change to its reservation system for 2026. Now, campers will be able to book four consecutive nights at the same site online. This change eliminates the need for visitors to call the office to extend their stay past one night, according to the park.

Summer camping in Baxter State Park opens on a rolling four-month basis. The online portal now opens at 6 a.m. instead of 12 a.m. For more information, visit baxterstatepark.org.

Andy Cutko, director of the Maine Bureau of Parks and Lands, said reservations across the rest of the 12 state campgrounds have been strong.

Maine has seen 3 million annual visitors to its state parks in recent years, and this year, they might notice new facilities and bathrooms at some as a result of $50 million in federal funds. Two campgrounds that were closed last year for upgrades — Aroostook State Park and Cobscook Bay State Park — will be open again.

State parks open for camping May 18. Cutko said the state processed nearly 7,000 reservations on the first day of booking in February.

“It peaked at 245 reservations in a minute,” Cutko said.

He encouraged people who don’t have reservations yet to consider booking a weeknight trip or look at dates in September. He also suggested exploring lesser-known destinations, such as Peaks-Kenny State Park in Dover-Foxcroft or Warren Island State Park near Islesboro.

“There are still some nice sites available,” Cutko said.

KATAHDIN GAINS A LITTLE ELEVATION

Mount Katahdin will get a new summit sign — and a little extra height.

The elevation on the new sign will read 5,268 feet instead of 5,267.

“Astute observers or map collectors may have noticed that the elevation of this tallest point in Maine is not consistent between different signs, markers, and maps,” the park said in an online post. “The seemingly straightforward task of determining the most accurate (or ‘correct’) elevation of Katahdin for the purposes of our new sign is more challenging than one might expect.”

The exact peak elevation varies depending on the source, and even the map published by the park has changed over time, reading 5,268 since 2015. The park said the change on the summit sign reflects the most recent known field measurement made by the University of Maine.

“Some may view the enduring discrepancies between these informational sources as inaccuracies that should be corrected, but they also tell the story of our evolving knowledge or conceptions,” the park said.