BAR HARBOR, Maine (AP) The trail network at Maine’s Acadia National Park is now listed on the National Register of Historic Places.

The National Park Service said Thursday the listing recognizes 109 trails that cover 117 miles. The trail network becomes the largest system of trails listed on the register.

The park service said the trail system was recognized because of its historic significance and ties to the history of Mount Desert Island, where the park is located. Kevin Schneider, superintendent of Acadia National Park, said in a statement that the recognition “is a testament to not only the historic significance of these trails, but also the incredible dedication of the National Park Service staff, partners and volunteers who continue to preserve them.”

The park service worked for several years to nominate the trails to the register. It was approved last week.