The Road Island Diner is a rare classic Streamline Moderne 60' x 16' Art Deco diner car restaurant located in the remote mountain city of Oakley, Utah, in the United States.

[2] After the Fair, It was sold to Al McDermott who had it towed it to Fall River, Massachusetts, where it operated for 14 years.

It is said to be the only pre-war, Art-deco streamline (constructed to mimic a rail dining car) diner west of the Mississippi River.

The Road Island Diner (O'Mahony Dining Car #1107) was added to the National Register of Historic Places by the National Park Service on August 21, 2009.

For other historic diners in the same architectural style see: Cramer, Alexander (July 7 2021).