The calculated distance (air line) between Buchholz in der Nordheide and Ahlerstedt is approximately 18 miles respectively 29 kilometers.
By car or train, the actual journey to Ahlerstedt is certainly longer, as only the direct route (as the crow flies) between Buchholz in der Nordheide and Ahlerstedt has been calculated here.
Air line (approximately)
29 kilometers
16 nautical miles