The calculated distance (air line) between Lucan and An Muileann gCearr is approximately 38 miles respectively 62 kilometers.
By car or train, the actual journey to An Muileann gCearr is certainly longer, as only the direct route (as the crow flies) between Lucan and An Muileann gCearr has been calculated here.
Air line (approximately)
62 kilometers
33 nautical miles