The small tunnel crossing the upgraded line Cologne-Düren
(<a href="http://www-users.rwth-aachen.de/christoph.schmitz2/strecke/strecke.html">ABS 4</a>)
east of the Erfttalstra&szlig;e near Sindorf seen from the south side on 20 May
2002. Under the highspeed tracks in the background the tunnel is already
finished. In the past, the old line passed in the foreground on a steel bridge.
While it is out of service, the tracks are removed here to build the new
tunnel. Soon an outer shell will be installed, then the room between them
(where the steel rods are already present) will be filled with concrete to form
the walls and the ceiling.
<p>
Digital photo by
<a href="http://www-users.rwth-aachen.de/christoph.schmitz2/index.html">Christoph
Schmitz</a>