For the first time in its nearly two-decade history, the bus system connecting Acadia National Park and Mount Desert Island will open three routes for a spring season beginning around Memorial Day weekend.
Following Acadia’s busiest year to date, with more than 4 million visitations in 2025, the Island Explorer — a fare-free shuttle service operating between the park, mainland and various MDI communities since 1999 — will begin its season early this year in the latest effort to manage the crowds that descend on the island each spring.
The Island Explorer, a 34-vehicle fleet operated by nonprofit transit provider Downeast Transportation, has historically provided services to MDI from late June through mid-October.
But this spring, as the region braces for the yearly wave of tourists, the mostly propane-powered bus system will begin running three routes on May 20. Last year the system received 72% of its funding from park entrance pass revenue.
Since the Schoodic Woods Campground — the park’s only mainland campsite — opened several years ago, the shuttle service has operated its Schoodic Route starting just before Memorial Day weekend.
While the Schoodic Peninsula has long been known as one of Acadia’s more secluded and quieter regions, it has also seen a rise in visitations in recent years. As it has in previous years, the Schoodic Route will begin May 20, with stops including Winter Harbor, Schoodic Point and Prospect Harbor.
But unlike previous seasons, visitors this spring will have access to a shuttle traveling from Trenton’s new Acadia Gateway Center — which had a soft opening in September 2025 after months of construction-related delays — to Bar Harbor, stopping along the way at campgrounds and visitor centers, including an aquarium.
Once on the island, visitors can take the Explorer’s Park Loop Road route, which also opens early this year, from the Hulls Cove Visitor Center to various trailheads along the scenic 27-mile drive.
Paul Murphy, Downeast Transportation’s executive director, said the May 20 opening of the new $27 million Gateway Center triggered the expanded schedule, though his group has long received requests to extend its service beyond its traditional late June through Indigenous Peoples’ Day season.
The director said his group also plans eventually to provide an express shuttle from Trenton to Bar Harbor and Southwest Harbor, though he noted they would need additional funding, employees and buses for that to happen. In the long term, Murphy hopes to add an Island Explorer shuttle that reaches Ellsworth.
Although the service has previously struggled to hire the 120 drivers they need for each season, because of the island’s high seasonal housing costs, they’re on track to meet that goal this year, Murphy said.
That’s partly because Friends of Acadia, a park advocacy group, and the National Park Service have raised millions of dollars to support housing Acadia’s seasonal employees, including Island Explorer bus drivers.
In July 2024, Friends of Acadia purchased a property with six two-bedroom townhomes on Jordan River Road, prioritizing bus drivers because of its proximity to the Gateway Center. Some drivers have also stayed at Southwest Harbor’s White Birches Campground, which the advocacy group helped upgrade to accommodate employees traveling by RV.
Around 10% of Island Explorer bus drivers live in some form of accommodations provided by Friends of Acadia and the park, Murphy said.