The calculated distance (air line) between Katwijk aan den Rijn and Eindhoven is approximately 69 miles respectively 111 kilometers.
By car or train, the actual journey to Eindhoven is certainly longer, as only the direct route (as the crow flies) between Katwijk aan den Rijn and Eindhoven has been calculated here.
Air line (approximately)
111 kilometers
60 nautical miles