Closely-guarded secret | Mike Higginbottom Interesting Times
Box Tunnel time-lapse video of track lowering and renewals 18 July - 1 September 2015 - YouTube
Box Tunnel - Wikipedia
The history of Box Tunnel, Wiltshire - Network Rail
🎈Happy birthday to Box Tunnel, one of Isambard Kingdom Brunel's most celebrated structures. It opened to through traffic on this day in 1841...and... | By Network Rail | Facebook