A 1922 Spanish Colonial Revival depot built by the Union Pacific, the Ontario station is one of the most attractive small-city train depots in Southern California — red-tile roof, stuccoed arcade, palm trees in front. It is still in active use as an Amtrak stop on the Sunset Limited route, though only twice a week in each direction.
Best appreciated from the outside; the waiting room has a single open hour around train times. Listed on the National Register.