Robert Gerwig, a civil engineer who specialized in designing railways for unusually challenging terrain, was born in the city of Karlsruhe in the Grand Duchy of Baden (now part of the state of Baden-Württemberg in southwestern Germany). Gerwig studied civil engineering at Polytechnische Schule (the present-day University of Karlsruhe), and initially focused on road construction.
Over time, however, Gerwig redirected his considerable expertise and energies to the development of railways. He became one of the principal designers of the Black Forest Railway, which was built between 1863 and 1873 in the region where he lived.
In drawing up plans for this railway, Gerwig was faced with a key task: how to contend with the formidably steep grades within the trees-dominated mountain range that constitutes the Black Forest. Gerwig ended up designing numerous loops and curved tunnels for the railway that would enable trains to avoid those steep grades. When completed, the Black Forest Railway helped significantly reduce the travel time for people making their way through the area. It remains the only mountain railway in modern Germany to be constructed with two tracks.
Gerwig adopted a similar design approach while helping to develop the trans-alpine Gotthard Railway in Switzerland. One of his major innovations for this project involved coming up with plans for a double loop in the section of the railway near the municipality of Wassen; this double loop has made it easier for trains to handle the climb in this rocky and high-altitude area. Gerwig also helped design the Höllental Railway, which runs through part of the deep Höllental valley in the Black Forest and encompasses some of the steepest railway grades found anywhere in Germany.
Gerwig, who died in 1885, also had a strong enthusiasm for clocks. He served as the first director of the Clockmakers School in the community of Furtwangen in the Black Forest region, and he also amassed a large personal collection of clocks. His collection can be seen today at the German Clock Museum in Furtwangen.