Rescuers used wires, ropes and pulleys to hoist themselves up to the stranded passengers when the tourist attraction was hit by problems at 5pm.
The trapped riders included a family of four with a two-year-old son who could not be rescued until after 9pm. They were lowered down with ropes onto a waiting boat in the river below.
Another cable car with two American tourists inside was reached by rescuers at 8pm. The cousins, aged 22 and 23 from New Jersey, also abseiled down onto a boat.
The darkness and strong winds made the rescue tricky. Emergency services initially wanted to pull the cabins manually across the river to the right bank of the Rhine. But that idea failed, meaning those stranded had to abseil down.
The Köln Stadt-Anzeiger reported it was the last cable car service of the day and only two of the cabins were occupied.
The cable car, which was built in 1957, runs 930 metres from Cologne Zoo to an area called Rheinpark on the other side of the river.
Investigators are unsure what caused the sudden stoppage, but are probing reports it was caused by high winds.
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