On Thu, 10 Apr 2008 20:10:01 +0100, Mr Thant wrote

It would appear there are three double track tunnels:
http://prints.leics.gov.uk/low.php?xp=media&xm=670835

One is obviously still in use, and the other two must have been for
when there was a big freight operation at Marylebone.


IIRC the Lords tunnel was never used - or am I mistaken?