Very nice, that mast is located on top of Fire Station 2. The mast is also equipped with the Cologne Fire Department's 2 meter (dispatch/several tactical frequencies is located in the 86 Mhz range) and 4 meter antenna relays (172-173 Mhz range, more tactical channels). This is a secondary radio relay/repeater that covers southern Cologne, the main mast is located on top of Fire Station 5 in Weidenpesch. You can see the mast in the right of the pic below: http://www.feuerwache2.de/themes/DeepBlue/images/fw2.jpg
I passed by this site today and took the following pic: http://gallery.wirelessadvisor.com/showimage.php?i=2503