The calculated distance (air line) between An Muileann gCearr and Roscrea is approximately 44 miles respectively 71 kilometers.
By car or train, the actual journey to Roscrea is certainly longer, as only the direct route (as the crow flies) between An Muileann gCearr and Roscrea has been calculated here.
Air line (approximately)
71 kilometers
38 nautical miles