Per TripAdvisor, the rankings of the world's Top 5 zoos are:
1. Henry Doorly (Nebraska)
2. San Diego Zoo (California)
3. Loro Parque (Spain)
4. St. Louis Zoo (Missouri)
5. Singapore Zoo
Too bad one of the my favorite zoos, the Smithsonian National Zoo in Washington DC, didn't make the list. But now I have a reason to visit Nebraska!