 US 1 and SR 3 run concurrently for over from Belfast through Bucksport, crossing the Penobscot Narrows Bridge over the Penobscot River.SR 15 joins US 1 and SR 3 in downtown Bucksport and splits to the south in Orland after .US 1 and SR 3 continue along the Acadia Highway to the city of Ellsworth.