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PianotondoAndTraviSpiralTunnelsOnSouthernRampOfGotthardbahn. en Outline of the Pianotondo and Travi spiral tunnels between Lavorgo station and former Giornico station Giornico vecchio on the southern ramp to the Gotthard tunnel from km to Gotthardbahn in Rll Freiherr von Enzyklopdie des Eisenbahnwesens Band Berlin Wien digitized