Abstract: A trailer hitch system utilizing a support member which includes a well that is accessible at the exterior of a vehicle. The support member is connected to the frame of the vehicle. A hitch element including a base portion, is capable of lying within the well of the support member such that a fitting for hitching a trailer is available for use external to the well. A lock removably holds the hitch element to base portion within the well. Thus a variety of hitch elements are interchangeable with the present assembly system.