The calculated distance (air line) between Neunkirchen and Klagenfurt am Wörthersee is approximately 113 miles respectively 181 kilometers.
By car or train, the actual journey to Klagenfurt am Wörthersee is certainly longer, as only the direct route (as the crow flies) between Neunkirchen and Klagenfurt am Wörthersee has been calculated here.
Air line (approximately)
181 kilometers
98 nautical miles