The calculated distance (air line) between Foix and La Seu d'Urgell is approximately 43 miles respectively 68 kilometers.
By car or train, the actual journey to La Seu d'Urgell is certainly longer, as only the direct route (as the crow flies) between Foix and La Seu d'Urgell has been calculated here.
Air line (approximately)
68 kilometers
37 nautical miles