What innovation or invention made suspension bridges possible?

The innovation that made suspension bridges possible is the use of cables to support the weight of the bridge deck. This innovation allowed bridges to be built over longer spans than was possible with previous bridge designs. The first suspension bridge was built in China in the 6th century AD. This bridge was made of bamboo and rope, and it spanned a distance of about 100 feet. The first suspension bridge made of metal was built in England in the 18th century. This bridge was made of iron, and it spanned a distance of about 100 feet. The first suspension bridge made of steel was built in the United States in the 19th century. This bridge was made of steel, and it spanned a distance of about 1,500 feet. The use of cables to support the weight of the bridge deck has allowed suspension bridges to be built over longer and longer spans. Today, the longest suspension bridge in the world is the Akashi Kaikyo Bridge in Japan. This bridge spans a distance of about 2 miles.