Lincoln Park is one of the most underrated zoos in the country. It feels weird to call a zoo that receives well over 3 million annual visitors in one of the worlds largest cities underrated, but so many times has this place been blown off in favor of the much larger Brookfield and theres this notion that the exhibit quality isn't as good. In reality, theres not a single bad exhibit left in the whole zoo and even being land locked on about 30 acres, the zoo still comfortably fits giraffes, rhinos, wolves, lions (in a few months), seals, two species of bear, two species of great ape, several species of hoofstock, over a dozen different small primates, houses for reptiles and small mammals and birds etc (plus a few rarities such as Puerto Rican parrots, kagu, aardvark, red wolves and others) all in exhibits that range from good to good to fantastic. Theres beautiful historic buildings that has been preserved with modern designs and in the past five years all of the crappy exhibits (lion house, bear grottos, seabird house) have been replaced thanks to a multi million dollar revamp of a large portion of the zoo.
There are a few minor blemishes of course. The primate house isn't bad but keeping that any species indoors year round is not great and there really isn't anything special besides the wonderful architecture. The hoofstock yards are pretty unremarkable, and the all indoor pygmy hippo exhibit needs work as well. I also find the rhino complex to be a bit small. But those are all minor issues in an otherwise fantastic zoo. Solid collection, no bad exhibits, several great exhibits, great historical heritage, great location, affordable etc. All the makings of a great zoo.