Zoo
It's one of the oldest Zoo's in Germany. It's situated close to the cable-lift. It maybe nice to combine these two.
Address: Riehler Straße 173, tel.: +49 221 778 50 http://www.zoo-koeln.de/
Cable-lift
Take a trip with the cable-lift! It takes you over the river Rhine through the air from one bank to another. One entrance is close to the Zoo (just follow the signs). On the other site of the river you'll find a nice park and the 'Claudius Therme' (a big sauna). From April to October, 10.00 to 18.00 daily.
Address: Riehler Straße 180 http://www.koelner-seilbahn.de