Antique Black and White Private Mailing Card Postcard. Identified as the Mousam House in Kennebunk, Maine. Undivided back, unused. Condition: This is an original photo postcard, not a copy or reproduction. It is in excellent condition. Comments: The Mousam House, built in Kennebunk in 1750, is the oldest hotel in New England. Mousam House still stands and currently houses a nail salon.