Suspension bridges are used for bridge spans in excess of 350m.
 

Some of the world's longest bridge main spans are:

 
Plans had been approved to build a 3300m span suspension bridge across the Strait of Messina, but the scheme was mothballed. However the new Government, under Silvio Berlusconi, have indicated that they want to resurrect the project.

A number of early suspension bridges were designed without the appreciation of wind effects. Large deflections were developed in the flexible decks and wind loading created unstable oscillations. The problem was largely solved by using inclined hangers.
The suspension bridge is essentially a catenary cable prestressed by dead weight. The cables are guided over the support towers to ground anchors. The stiffened deck is supported mainly by vertical or inclined hangers.

Design Standards  |  Bridge Components | Choice of Deck