From a description on www.northantrim.com/carrick_a_rede.htm:
"Spanning a chasm some eighty feet deep is the famous Carrick-a-Rede rope bridge. It once consisted of a single rope hand rail and widely spaced slats which the fishermen would traverse across with salmon caught off the island.
The single handrail was subsequently replaced by a two hand railed bridge, [and] the current, caged bridge was installed by the National Trust during Easter of 2000 as a further safety measure.
Although no-one was ever injured falling off the old bridge, there have been many instances of visitors being unable to face the return walk back across the bridge, resulting in them being taken off the island by boat."