in Biddeford Maine there is a very old diner, the Palace Diner, and it's not only the oldest diner in the state, but the oldest restaurant as well

The original owner, Louis Lachance, was a locomotive engineer before switching to restaurateur and operating the diner until 1962.

The car was built specifically for Biddeford and has stood at several spots, all within a block of the current Franklin Street location, since then. It was a training dining car, and was made into a full-blown diner. 

https://www.palacedinerme.com/history

https://www.tastingtable.com/1942900/old-school-diners-worth-visiting/

https://wjbq.com/the-oldest-restaurant-in-maine-is-a-treasured-dining-car-in-biddeford/

https://toastykettle.com/2019/10/31/palace-diner-in-maine-with-chad-conley/

https://www.themainemag.com/2815-palace-diner/#close