The Athlone to Mullingar Cycleway (also known as Old Rail Trail) is a long-distance cycling and walking trail in County Westmeath, which forms a section of the Dublin-Galway Greenway. It is a 40 kilometres long rail-trail over the disused Athlone-Mullingar rail line beginning in Athlone and ending in Mullingar. A new bridge is planned for Athlone.
The Moate-Garrycastle section was officially opened by Taioseach Enda Kenny in October 2015. In September 2015 the Westmeath Independent reported that the greenway could provide a "€15m boost" to the local economy.
The section has been extended up to Ballymahon road (White gates) in December 2016 and will eventually extend into Athlone town.
Plans, by a community development organisation in Kilbeggan, County Westmeath, are underway to connect the Greenway to the Offaly Cycleways at Kilbeggan with a greenway to Tullamore, County Offaly. Work is planned to begin by summer 2016.