The calculated distance (air line) between Thalwil / Dorfkern and Lancy is approximately 139 miles respectively 223 kilometers.
By car or train, the actual journey to Lancy is certainly longer, as only the direct route (as the crow flies) between Thalwil / Dorfkern and Lancy has been calculated here.
Air line (approximately)
223 kilometers
121 nautical miles