Maine State Route 100 is an east-west highway in Southern Penobscot County. It runs from the Somerset/Penobscot County Line, near Newport, to Bangor. ME St Rt 100 passes through the following towns in Penobscot County. Newport Etna Carmel Bangor ME St Rt 100 is multi-plexed in Penobscot County. Maine State Route 11, from the Somerset/Penobscot County Line to Newport. U.S. Rt. 2, from Newport to Bangor.