One of the nation's premier zoos, the San Diego Zoo offers more than 3,700 animals, representing more than 650 species and subspecies. Yep, even a few frogs! The zoo is big on conservation, and its Institute for Conservation Research has reintroduced more than 30 endangered species back into the wild.

Because of its hilly, predominantly tropical terrain, you will likely find a day at the zoo is a full workout, so make sure to wear your comfortable walking shoes. Don't let this stop you from making the trip! There are so many not-to-miss San Diego Zoo exhibits and attractions, including the lush grounds themselves, which the zoo maintains as an arboretum. On site are many rare plants, some of which are grown to feed the animals (hello, pandas). The zoo is situated within the beautiful Balboa Park, a destination on its own, with museums, botanical gardens, restaurants, trails and open space. Basically, it's a nature and animal-lovers paradise!

Here is our list of not-to-miss San Diego Zoo Exhibits & Attractions:

1. Guided bus tour

While it's not an exhibit, this 35-minute tour takes you through most of the park aboard an open-air, double-decker bus. It's a great way to get the lay of the land, so to speak, and a terrific overview of the park. Take the Guided Bus Tour first thing in the morning and then set out for your desired destinations.

2. Pandas

More than anything else, the San Diego Zoo is known for its pandas, which have been on loan from China since 1996. The giant panda is endangered in the wild, and only about 1,600 are known to live on Earth. Thanks to its successful breeding program, six pandas have been born at the San Diego Zoo! Today, three giant pandas call the zoo home, including Bai Yun, who is mother to the first surviving giant panda in the United States!

3. Polar bears

The San Diego Zoo is home to three playful polar bears. Certainly one of the coolest places to view the polar bears is the underwater viewing room. They might just swim up to say "hi!" You can also watch them outdoors in their tundra habitat. Finally, get up close at the Experience Wall, where keepers open up the glass panels and interact with the polar bears through a mesh barrier for a truly up-close experience.

4. Skyfari Aerial Tram

Did we mention the San Diego Zoo is very hilly? One of the shortcuts for getting across the park is the Skyfari Aerial Tram, which offers spectacular views of the zoo and surrounding Balboa Park. It's a real treat, and your feet will thank you.

5. Koalas

Besides the frog, my favorite animal has always been the koala. So, of course, it's on my list. But even cooler is the San Diego Zoo's newest exhibit, Conrad Prebys Australian Outback, known more affectionately as Koalifornia. The Australian Outback area, which opened in May 2013, is double the size of its former exhibit and offers hands-on activities plus great views of my favorite marsupial. From the deck of the Queenslander House, you'll be eye level with the koala colony. You can also explore the Outback and see other Australian marsupials such as wombats and wallabies, Tasmanian devils and kookaburras.

6. Elephant Odyssey

This 2.5-acre elephant habitat includes both African and Asian elephants in a natural, open area that gives them plenty of room to roam. Inside the Odyssey, you'll find the Elephant Care Center, where you can watch zoo keepers providing routine care to the animals. After you visit the care center, let the kids burn off some energy in the Elephant Play Area, which features a maze, play fossil dig and puzzles.

7. Giraffes

Some of our favorite animals at the zoo are the giraffes, maybe because they're so tall and we're so short, but we never miss out on a chance to see them. At the San Diego Zoo, you'll find a small herd of Masai giraffes within the Urban Jungle exhibit. Best of all, you can join in feeding the giraffes at certain times of the day! Be sure to check the schedule when you visit.

8. Scripp's Aviary

Nestled inside this lush, African rain forest, you'll find more than 130 African native birds representing 35 different species inside this 80-foot-tall aviary. Let the tranquil sounds of the rushing water from the falls

9. Orangutan

Get ready to go nose to nose with the playful orangutans, who sometimes like to sit close to the observation area so they can watch the humans on display :) The world's largest fruit-eating animals are very playful, and within their exhibit you might catch them traversing their ropes or nets, munching on some tasty mustard, honey or barbecue sauce out of their "termite mound," or climbing their vertical sway poles. No matter what they are doing, they always seem entertaining!

We hope you've enjoyed our look at the not-to-miss San Diego Zoo exhibits and attractions. Ready to go? Purchase your San Diego Zoo tickets now! If you're looking for help planning your trip, start with our San Diego Planning Guide, which includes all of the area major attractions. 

Hoppy planning!