The calculated distance (air line) between Sri Jayewardenepura Kotte and Vavuniya is approximately 135 miles respectively 218 kilometers.
By car or train, the actual journey to Vavuniya is certainly longer, as only the direct route (as the crow flies) between Sri Jayewardenepura Kotte and Vavuniya has been calculated here.
Air line (approximately)
218 kilometers
117 nautical miles