Suspension bridges link many valleys and mountain passes together. They are used primarily as trade and pedestrian routes.
If you are going trekking in Nepal then there's a very high chance you'll have to cross a suspension bridge. Generally safe suspension bridges in Nepal are constructed with galvanized steel, iron and have concrete bases at either end.
Original suspension bridges in Nepal still exist and are constructed from bamboo and wood. Many of the larger suspension bridges in Nepal today have been funded by overseas donors.
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