@SailfinDragon Here is an excerpt from my Potter Park Zoo review on my 2012 Road Trip thread:
Feline/Primate House – This structure opened in 1930, just one year after the Bird & Reptile House, and it is slightly odd to have such a small zoo with a pair of buildings that are more than 80 years in age and still standing. There are 3 feline enclosures along one side of the building (snow leopard, Amur tiger – including a trio of 10-month old cubs, and African lion) and two enclosures on the other side of the building (mandrill and ring-tailed/red ruffed lemur). The big cat exhibits are not aesthetically pleasing to the eye as they are essentially large metal cages, but they have lots of foliage and are well furnished. The lemur and mandrill outdoor enclosures do not fare so well and the mandrill exhibit in particular is mainly mock-rock.
It is like stepping back into time when one enters the building as while it was renovated in 1989 it is not common to have big cat houses allow visitors to still see the inner workings. A puny golden lion tamarin exhibit is built into a wall; a mongoose lemur cage dominates one end of the central section, and there is a carpeted walkway to view the 5 indoor holding areas to see if the felines and primates are indoors escaping the heat. The indoor enclosures are almost empty for the big cats and the primates only have a smattering of ropes and enrichment opportunities as they are also fairly bare.