There are many good photographs in An Illustrated History of Carlisle's Railways by WAC Smith and Paul Anderson capturing among other things the massive and impressive gothic endscreens that went.Shame. Must have been an even more magnificent station than now !
According to "Rail Centres - Carlisle" by Peter W Robinson (Ian Allan, 1986) the overall roof had become dangerous due to lack of maintenance over the war years and afterwards. In 1956/57 the roof was much reduced in size and the original end screens replaced.
The station was known as Citadel but just about managed to avoid flattening the castle - unlike its counterpart at Berwick.Hadrian built it to keep the Picts out!
Historic England said:Heritage Category: Listed Building Grade: II
List Entry Number: 1209674
Date first listed: 11-Apr-1994
List Entry Name: DETACHED WEST WALL OF CITADEL STATION