Yorkshire gauge change
Richard Parker comments that changing gauge en route was perhaps not a new technology 20 years ago ( Open Access, RAIL 911).
In fact, UK patent 8959 of 1906, granted to Spencer and Dawson of Bradford, led to a through Leeds-Bradford public tram service that ran from April 22 1907 until March 1918, despite Leeds using standard gauge and Bradford using 4ft 0in gauge.
I think that Yorkshire rather pipped Spain to the post on that one. (Information from Leeds Transport, Volume Two, by the late Jim Soper, published by the Leeds Transport Historical Society.)
Dave Hodson, Derby