Where are eyrie and trenches found

This is mainly due to the fact that there are still innumerable factories and tanneries as well as dye works on the upper course of the trench, and the dirty water of the trench consequently appears alternately now green, now blue, now in a mixture of colors that cannot be identified. "

The filling

A cabinet resolution of June 6, 1883 approved the filling of the Green Trench and ordered the start of the work.
The part from the Spree to Leipziger Strasse was tackled first after some difficulties with residents who had still drained into the ditch and thereby delayed the work had been overcome. In the late summer of 1883, when a low water level made the work easier, the filling began. The areas obtained in this way were sold to the residents, the city itself bought the areas of the trench located at the Cöllnisches Gymnasium to enlarge the Cöllnischer Park.
The backfilling should have been completed in 1885, exact dates could not yet be found.
Only the parts under the bridges were only filled in in 1886 when they were demolished. In 1889, the city took over the historic building of the Wusterhausen Bear, which stood on the terrain of the filled in Green Trench, which is now located in the courtyard of the property at Neue Jakobstrasse 10. Four years later, the small tower was moved to the Cöllnischen Park, where it can still be admired today as the last remnant of the Berlin fortress.