The Baltimore and Ohio Railroad Museum's prized 4-4-0 No. 25, an 1856 Mason Machine Works survivor is seen here at the Museum's back shop undergoing its mandatory 1472 service inspection and overh... (more)

The B&O #25 - the "William Mason" is America's oldest operational steam engine. She is seen here under steam at the &O Railroad Museum on a beautiful Fall day making short solo runs by the Museum... (more)

A Civil War soldier gives salute to the B&O #25, the "William Mason", America's oldest operational steam engine (built in 1856) during the B&O Railroad Museum's Railfest Steam Days.

Over 150 years old, B&O 25, The William Mason, can still put on a show, as it did last year passing the passenger car shops during the B&O Railroad Museum's Steam Days.

B&O's "William Mason" wears its movie livery, "Wanderer" for its starring role in "The Wild, Wild West."

the "William Mason" on its return from Camp Carroll and a Civil War Encampment.