Rescued from closure in 1997 by the extraordinary Heap family, this small zoo offers a rather different experience from Regents Park. There are only a small number of animals and none that cannot stand the cold of South London - but they are all cute and you can observe them running about, swimming, and building stuff in a natural environment. You can also pick many of them up.
There's something rather cute and Mom-and-Pop about a zoo that makes a big deal out of peacocks, but Battersea has a few exotics as well including lemurs and meerkats. One thing about having only small mammals is that they look comfortable and happy, and respond to their keepers. This is a karmic zoo.
Not the most incredible menagerie but well worth a visit with an animal lover (especially those of the child variety) and the park outside the zoo is perfect for a medium sized walk as well.