The calculated distance (air line) between Floridsdorf and Klagenfurt am Wörthersee is approximately 149 miles respectively 240 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 Floridsdorf and Klagenfurt am Wörthersee has been calculated here.
Air line (approximately)
240 kilometers
129 nautical miles