High Quality Content by WIKIPEDIA articles! An observation car/carriage/coach (in US English, often abbreviated to simply observation or obs) is a type of railroad passenger car, generally operated in a passenger train as the last carriage, with windows on the rear of the car for passengers` viewing pleasure. The cars were nearly universally removed from service on American railroads beginning in the 1950s as a cost-cutting measure in order to eliminate the need to "turn" the trains when operating out of stub-end terminals.