The calculated distance (air line) between Sri Jayewardenepura Kotte and Panadura is approximately 12 miles respectively 19 kilometers.
By car or train, the actual journey to Panadura is certainly longer, as only the direct route (as the crow flies) between Sri Jayewardenepura Kotte and Panadura has been calculated here.
Air line (approximately)
19 kilometers
10 nautical miles