Gotthardbahn: Boscierina Tunnel mit Polmengo Brücke by Adolphe Braun and Cie https://www.rawpixel.com/image/14314088/gotthardbahn-boscierina-tunnel-mit-polmengo-brucke-adolphe-braun-and-cieFree Image from public domain licenseGezicht op de Alte Brücke over de rivier de Main te Frankfurt am Main (1742 - 1801) by Georg Balthasar Probst, anonymous… https://www.rawpixel.com/image/13778414/image-paper-cloud-artFree Image from public domain licenseGotthardbahn: Brücke über die Göschenenreuss by Adolphe Braun and Cie https://www.rawpixel.com/image/14316130/gotthardbahn-brucke-uber-die-goschenenreuss-adolphe-braun-and-cieFree Image from public domain license