The calculated distance (air line) between Fürstenfeld and Klagenfurt am Wörthersee is approximately 89 miles respectively 143 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 Fürstenfeld and Klagenfurt am Wörthersee has been calculated here.
Air line (approximately)
143 kilometers
77 nautical miles