The calculated distance (air line) between Madhyapur Thimi and Chautārā is approximately 21 miles respectively 34 kilometers.
By car or train, the actual journey to Chautārā is certainly longer, as only the direct route (as the crow flies) between Madhyapur Thimi and Chautārā has been calculated here.
Air line (approximately)
34 kilometers
18 nautical miles