In rail terminology, a through coach is a passenger car (coach) that is re-marshalled during the course of its journey. It begins the journey attached to one train, and arrives at its destination attached to another train.[1][2]
Through coaches save their transit passengers the need to change trains themselves.[1] They also increase the number of direct links offered by the train operator(s).[2]
Most frequently in the form of sleeping or couchette cars, through coaches have commonly been used for long-distance journeys, especially in continental Europe, although they are much less common now than they were in the early 1970s.[2]