The Ha'penny Bridge was erected in 1816 to replace ferries which brought Dubliners across the River Liffey.
It was said to be the first cast iron metal bridge in Ireland and was cast in Coalbrookdale in Shropshire, England.
Pedestrians paid a toll of a ha'penny to ensure a safe river crossing which matched the charges levied by the ferries.
The toll was eventually dropped in 1919. The bridge was the only pedestrian bridge on the River Liffey for 184 years, until the Millennium Bridge was opened in 2000.