Narrower Terms (13)

• Anacostia River Valley (Md. and Washington, D.C.)
• Choptank River Valley (Del. and Md.)
• Cumberland Valley (Md. and Pa.)
• Green Spring Valley (Md.)
• Little Cove Valley (Pa. and Md.)
• Long Green Valley (Md.)
• Middletown Valley (Md.)
• Octoraro Valley (Pa. and Md.)
• Patapsco River Valley (Md.)
• Patuxent River Valley (Md.)
• Pocomoke River Valley (Del. and Md.)
• Severn River Valley (Md.)
• Youghiogheny River Valley