There is widespread traffic diversions in Connemara following the collapse of a bridge in the centre of Leenane.
Motorists are being warned that they now face diversions of over 110km.
The century old stone arched bridge on the main Clifden to Westport road collapsed shortly before 5pm.
Galway County Council says one of the arches was swept away following three hours of torrential rain; the second arch collapsed a short time later.
The N59 road through the village is now closed.
Local residents say it is a miracle that nobody was injured by the collapse.
The road is one of the busiest in west Galway and carries a very large volume of tourist traffic.
The council says it will be examining the possibility of a temporary bridge but this could take a considerable time to put in place.