Key facts

• The engineering challenge and Carl von Ghega (1802–1860): the Semmering railway was designed by Karl Ritter von Ghega (Carl von Ghega), a Viennese engineer of Albanian origin who had studied American railway engineering (he had inspected the Baltimore and Ohio Railroad and the Western Railroad of Massachusetts during an 1842 study trip to the United States) — the Semmering Pass presented a maximum gradient of 25‰ (25 metres of rise per 1,000 metres of horizontal distance), which was widely regarded as impossible for steam locomotives of the 1840s; von Ghega solved the problem by using a combination of long curves (radii of at least 190 metres to manage the gradient), bridges and viaducts to maintain a consistent gradient across valleys, and tunnels through the highest ridges; the construction workforce of approximately 20,000 workers (including many Italian and Bohemian labour migrants) built 14 tunnels totalling 4.4 km, 16 major viaducts, and approximately 100 smaller stone arch bridges in just 5 years (1849–1854); von Ghega was ennobled by Emperor Franz Joseph I for the achievement; he is depicted on the Austrian 20-schilling banknote (1967–2001)
• The “Battle of the Locomotives” (Semmeringer Probefahrten, August 1851): the most famous locomotive competition in railway history — before committing to a design for the Semmering section of the Southern Railway, the Austrian Railway Administration organized an open competition in August 1851 at the Semmering Pass: any engineer or manufacturer could enter a locomotive capable of hauling a 140-tonne load over the Semmering Pass at an average speed of 11.5 km/h; four locomotives competed in the trial, each making multiple runs over the pass: the Bavaria (designed by Wilhelm von Engerth and built by Günther & Co., Wiener Neustadt), the Vindobona (designed by Joseph Hall, built in Vienna), the Bavaria again (note: a different machine), and the Neustadt (designed by Karl Meyer); the Bavaria (von Engerth design) won; the von Engerth locomotive type — characterized by a large fixed wheel arrangement supporting the boiler and a pivoting rear bogie carrying the firebox — became the standard for mountain railway locomotives for the next 30 years and was built in hundreds of copies; the winning locomotive Bavaria is preserved at the Vienna Technical Museum
• The 14 tunnels and 16 viaducts: the signature engineering structures of the Semmering Railway — the longest tunnel is the Otter tunnel (1,430 metres; the only tunnel on the line that required artificial illumination throughout — earlier tunnels were short enough to be lit by daylight from the portals); the most photographed viaduct is the Kalte-Rinne (also known as the Schwarza viaduct; 116 metres long, 46 metres high; 10 semicircular arches in local sandstone; the Romanesque Revival arch form was the architectural fashion for Victorian railway engineering across Europe, creating a visual language of “ancient permanence” for new industrial structures); the Weinzettelwand viaduct (the longest on the line at 195 metres) passes through a narrow gorge where only the railway exists; the Adlitzgraben viaduct curves around a headland above a valley; together the viaducts represent the full range of 19th-century masonry bridge engineering
• The Semmering resort (Belle Époque–Art Nouveau, 1880s–1914): the secondary cultural significance of the Semmering Railway — after 1854, the railway made the cool alpine climate of the Semmering Pass accessible from Vienna in under 2 hours; the area rapidly became the most fashionable summer resort of the Habsburg aristocracy and the Viennese upper bourgeoisie; the grand hotels of the Semmering (Panhans Hotel, 1888; Südbahnhotel — now the Hotel Semmering, 1882; Kurhotel, 1909) are the largest surviving complex of Belle Époque/Historicist resort architecture in Austria; the Semmering was the preferred summer retreat of Arthur Schnitzler, Sigmund Freud, Gustav Klimt, Egon Schiele, and many other figures of Viennese intellectual and artistic life in the Fin de siècle; the Semmering landscape and the railway also appear in several paintings by Klimt and Schiele
• Heritage: UNESCO World Heritage Site, Semmering Railway, inscribed 1998 (the first railway in the world to receive a UNESCO WHS inscription)
• GPS: 47.6401° N, 15.8320° E (Semmering Pass summit)