On 8 March 1858 the line was extended to Birr and became a junction when the line to Nenagh was opened on 5 October 1863 eventually forming a new through route to Limerick via Nenagh.
In 1858, the railway line reached Birr. It later became a junction point when the line to Nenagh was inaugurated in 1863. This created a new direct route from Birr to Limerick via Nenagh.