The remains of a similar bridge exist at Janglache; but there are no wooden or twig suspension bridges over the Tsanpo.
the Tali-Bhamo caravan route, described by Colborne Baker, crosses the river by one of those iron suspension bridges which are a feature of Yun-nan, at a height of 4700 ft.
One of the most interesting topics of study is the trails along which the seasonal and annual migrations of tribes occurred, becoming in Peru the paved road, with suspension bridges and wayside inns, or tambos.
In suspension bridges the principal members are in tension, and the introduction of iron link chains about the end of the 18th century, and later of wire ropes of still greater tenacity, permitted the construction of road bridges of this type with spans at that time impossible with any other system of construction.
On the other hand, suspension bridges require lofty towers and massive anchorages.