Roof luggage holder for a motor vehicle roof

The roof rack has longitudinal bars (1,2) connected mutually and to a cross beam (3) through a pivot joint. Each of the bars has interlocking elements (11B) arranged in the vehicle longitudinal direction at the same height as the pivot joint and mounted rigidly on the cross beam. An end of another interlocking element is rotatably arranged in the cross beam about an axis parallel to the axis of pivot joint and is set longitudinally movable, to engage with the other interlocking elements.