The village is named after Saint Moling (or Mo Ling, 614–697), who founded a monastery there in the early 7th century.

[citation needed] A 9th-century high cross, showing the crucifixion and a Celtic spiral pattern, stands outside the remains of the abbey.

[citation needed] As well as being visited by anglers, St Mullins is one of the stop-off points for pleasure barges and cruisers who transit the River Barrow.

[citation needed] The horses and carts came down the tracks from the Blackstairs Mountains to gather their supplies and sell their goods for export.

[citation needed] St Mullins is also the beginning and ending point for the Barrow Way long distance walk.