The calculated distance (air line) between Schalksmühle and Wermelskirchen is approximately 15 miles respectively 25 kilometers.
By car or train, the actual journey to Wermelskirchen is certainly longer, as only the direct route (as the crow flies) between Schalksmühle and Wermelskirchen has been calculated here.
Air line (approximately)
25 kilometers
13 nautical miles