The calculated distance (air line) between Neusiedl am See and Wiener Neustadt is approximately 30 miles respectively 48 kilometers.
By car or train, the actual journey to Wiener Neustadt is certainly longer, as only the direct route (as the crow flies) between Neusiedl am See and Wiener Neustadt has been calculated here.
Air line (approximately)
48 kilometers
26 nautical miles