The calculated distance (air line) between Monaragala and Dehiwala-Mount Lavinia is approximately 101 miles respectively 163 kilometers.
By car or train, the actual journey to Dehiwala-Mount Lavinia is certainly longer, as only the direct route (as the crow flies) between Monaragala and Dehiwala-Mount Lavinia has been calculated here.
Air line (approximately)
163 kilometers
88 nautical miles