They really need a large open field as their 'sister' group at Port Lympne now have(shared with Rhinos). I can see the door in the wall is open so they have access to both outdoor enclosures in the L shape. Presumably the other looks the same!
This is one of my least favourite Zoo buildings just about anywhere.. It was built for Apes (not so long ago either)- Gorillas and Orangutans, but the design was very poor- the indoors are dark and dungeon-like, while outdoors it used to be very difficult to see the animals because of a hedge, except at a couple of little 'view point' places.
No doubt it works okay as temporary(?) housing for this baboon group though they've quickly wrecked the outside areas and it looks pretty awful as a display.
baboons are typical for ripping up grass and turning it into this. guinea baboons often eat alot of grass and roots. and port lymnpe they only let the baboons out in the paddock on realy fine days.
Patas monkeys are equally capable of similar damage. When Zoo Boise layed new sod in the patas monkey enclosure, the patas monkeys rolled all of the sod up to one side of the exhibit in their search for insects.
I remember watching a program on television about this exhibit and how they laid out new grass as well as new branches and the barrels seen in this picture