Maine will be getting a $1.1 million grant to replace six of the 17 propane buses that serve Acadia National Park and surrounding communities.

U.S. Rep. Mike Michaud of Maine said the Federal Transit Administration grant has been awarded to the Maine Department of Transportation.

The money will go to the Island Explorer transit system, a seasonal bus service the connects the campgrounds and motels on Mount Desert Island with the island’s towns and popular destinations in the park.

The bus service started in 1999 and has been credited with cutting down on pollution while carrying more than 2 million passengers.