The Old "Elbtunnel" in Hamburg, 1907-11, is a work of engineering which was admired a lot at the time it was built. 23 meters below the soil, it crossed the river underneath and allowed thousands of workers to walk from the town where they lived to the forges, shipyards and docks. My husband, parents-in-law and I took a walk on Sunday. The picture no.2 is older, we did not have sunny weather.
After years of renovation, the tunnel has new elevators which can even take cars down und up again on the other side. I love the early 20th century architecture and the glass mosaics around the entrance doors.