Listed on the National Register of Historic Places in 2003, the Monarch/Owl Diner is located at 246 Appleton Street. The diner was manufactured by the Worcester Lunch Car Company (#749) in 1940 and was originally located in Waltham where it was known as the Monarch Diner. It was moved to Lowell in 1951 and has been added on to twice between 1952 and 1966. By 1954, the Owl was one of 16 diners operating in Lowell.
It is one of a very few examples of the semi-streamliner diner form remaining in Massachusetts and is the best-preserved. The Worcester Lunch Car Company was a major force in the design and construction of Massachusetts diners prior to World War II and introduced the semi-streamliner model as a conservative alternative to the streamliner diners that debuted in the late 1930s.