Citadel Railway station Carlisle - Citadel station was designed in 1847 in a Gothic style by Sir William Tite, the leading station designer of his age and the architect of London's Royal Exchange. It is now the northern terminus of the famous 72-mile Settle to Carlisle railway. At one time no less than seven railway companies had lines terminating in Carlisle and by 1880 they were all using the Citadel station.