Our 102nd Pic of the Week tells a story of how a bridge became a tunnel and how no one but the biker could tell of the change. This bridge-converted-to-tunnel is located in Jena, in the eastern German state of Thuringia and spans Ammerbach Creek, which runs through the southern suburbs of Ammerbach and Winzerla before it empties into the River Saale near the Ernst-Abbe-Sportsstadium. It was constructed during the same time as the railroad that connected Weimar with Gera with a regional hub station at Jena-Göschwitz- namely 1876. The stone arch span is no longer than 20 meters and has a height of six meters.
So how was the bridge „converted“ into a tunnel?
This was in connection with the reconstruction of the rail line between Weimar and Jena-Göschwitz and it had to do with a nearby bridge that was built in 1935, spanning Kahlaische Strasse, which was a combination of car and tram services. Because of structural instability due to age and the low clearance on the street, workers built a new bridge off site that was a meter higher and twice as long as the main span of 30 meters over the street. This does not include a tunnel on the west side of the street. The entire structure was then torn down, and the new span slid into place.
At the same time, this short-span crossing in the picture was rehabilitated and an additional one meter of railroad bedding was added in order to smooth the grading between the two bridges. A double-concrete railing was added on each side to allow for electrical wires to run through the top railing and to capture the falling rocks by the bottom railing.
This whole conversion and nearby bridge replacement happened from the fall of 2016 until the middle part of 2017 and resulted in detours of all kinds, from rail traffic all the way to the bike trail, which the now-converted tunnel crosses. Living in Winzerla for 15 out of the 20 years I spent in Jena, one can find the detours rather annoying unless you know some short cuts and detours to the city center by car or bike. But this was one that was part of the mega-project on several routes through Jena that brought 70% of the city’s total traffic to a standstill and increased the blood pressure of every driver and biker by an average of 45%! It was a bit over the top and still to this day, management could have been better.
In either case, with the water under the bridge, one can still enjoy this scenic view of the tunnel, now covered with vegetation after a a couple years of bare concrete and rock. Like the bridge, this tunnel comes up fast when you bike between the city center and the south of Jena, and one cannot see it right away- unless you make a stop, like I did with my family. This photo was taken last year, in 2019. And the weather was perfect for the pose. The original arch is still there, covered by bushes and trees. However, it is obvious that the structure has been converted into a tunnel. 😉 Nevertheless, one can enjoy the scenery with just the trains passing by. A real treat when you bike through Jena and along the River Saale. 🙂
The Holzlandbahn provides direct connection between Dresden and Düsseldorf via Chemnitz, Glauchau, Gera, Jena, Erfurt and Kassel. While regional trains run on this route mostly, plans are in the making to electrify the railline completely so that InterCity trains can use them by 2030. More information on the line’s history can be found here.