Yankari is Nigeria's best park for observing wildlife. With a bit of luck you may come across buffaloes, waterbucks, bushbucks, hyenas, leopards, plenty of baboons and the odd lion. While the park's animal population has suffered from poaching it still has some big drawcards, like the 500-strong population of elephants, and the birdwatching is excellent.
The best time to see animals is from late December to late April, before the rains, when the thirsty animals congregate at the Gaji River. You're permitted to drive your own vehicle if you take a guide, otherwise the park has a safari truck that takes two hour tours.
Yankari's other great attraction is the incredibly picturesque Wikki Warm Spring, near the park campsite. The crystal-clear mineral water is a constant 31°C, forming a lake 200m long and 10m wide and great for a swim.