This cage was excellent for the gibbons, apart from those hideous tiny concrete dens they had.
A similar cage at the other end housed various birds, on that occasion it had Australian Parakeets and Australian Crested Pigeons in it.
Certainly I would rank the current gibbon enclosure closest in appearance and design to this one in the UK - that for Gabriella's Gibbons up at Edinburgh Zoo - as the best gibbon enclosure in the UK.