Abstract: In order to provide protection to magnetic tape during storage and use, a tape holding cassette according to the invention has a closable housing within which there is disposed a movable entity consisting of a separating wall that can glide in suitable grooves within the housing. Mounted on opposite surfaces of the separating wall are tape reel holding and rotating hubs and further mounted on the separating wall are tape guiding mechanisms that guide the tape from one reel across the edge of the separating wall to the second tape reel, thereby defining a path in which the tape travels obliquely with respect to the plane of the housing. The tape reel hubs have gears that can engage corresponding gears of the tape recorder and they include internal locking mechanisms that automatically prevent relative rotation of the tape reels with respect to one another and with respect to the cassette during transport.