In most cases where rivers or ravines occur along regularly used paths, fixed bridges have been built in the course of time. The backpack bridge is conceived for a quite different situation. It is a response to the wish for independence and the urge to explore untrodden paths. The structure can be simply and spontaneously erected wherever obstacles occur, and afterwards dismantled and carried to the next place where it is needed. It is, therefore, ideally suited for expeditions, but it could also be used at trade fairs and exhibitions. Various alternative forms of construction were investigated in developing this prototype. In its present form, the bridge is based on a span of 10 metres and can bear the weight of two persons. A special feature of the design is the geometry of the trussing on the underside, which prevents the bridge swinging violently to one side under loading. The walkway is simply laid on top of this structure, and the bridge does not have to be fixed at the abutments. Admittedly, the fact that it yields slightly with each step – and probably does not comply with building laws – means that a certain sure-footedness is required in using it. Any stretching of the cables can be counteracted by winding them a number of times around the karabiners, thereby stressing the entire structure. Most connections consist of simple bored holes with split-pin fixings. The material foreseen for the construction is aluminium, but lighter metals and carbon-fibre-reinforced plastics are conceivable as well.