Although it is no longer free, it is a minimal charge. It is a great zoo for little kids and is easily walked in about an hour with toddlers in tow. My kids' favorite activity is the "Wild Bird Walkabout" where you feed the birds with a popsicle stick that has seeds stuck on it. The birds land on your arms and hands and the kids love it.
The Caldwell Zoo - For more pictures check out my travelogue!
The Caldwell Zoo in Tyler is one of only 2 FREE zoos in the United States. I've been to many pay zoos that aren't up to the quality and variety that the Caldwell Zoo displays. Even parking is free!
Many types and kinds of animals, birds, etc may be seen here.
Flamingoes and ducks from all over the world can also be seen.