San Diego zoo is supposedly one of the best in the world. The entrance fee is a hefty $56 but we were not disappointed - it’s like a nicely-landscaped amusement park.. The zoo is quite large so you can spend a whole day there!
Animals tend to nap a lot in the shade in the middle of the day (to avoid the heat). The best time to spot them are early in the morning and late in the evening so plan your visit accordingly.