Cologne Zoo--150 years of captive animal history

The commemorative gold coin above, celebrating the 150th birthday of the Cologne zoo is available for purchase.

In 1864, four years after the Cologne Zoo opened these gates with the Red Deer and the gable gated buildings was built. The photo above is from 1904 and the photo below is most likely a later date as an "arch" has been added between the deer. I have never seen a picture of the original gate, and if anyone has one, I would sure be grateful to see it.