that’s a good one, he must be a REALLY serious member of ‘Tunnel Soc.’ 
{now bookmarked in my london heritage section} go and check out one of the very first books exposuring the work of our spooks in the early 70s: “Beneath the City Streets’ by Peter Laurie reprinted in the 80s I think. He had the low down on Down Street and Brompton Road used in WW2 and the secret government bunkers under Kingsway in Holborn. it’s amazing how many of the stations mentioned are close to me, or rather how all the stations close to me are mentioned! Holloway Road, Drayton Park/Finsbury Park, Highbury & Islington, York Road, Angel, South Kentish Town and more stations not much further away. if York Road gets re-opened with Kings Cross redevelopments then it will add a minute or two on to all my journeys.
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