Pachy's answer is correct, though I would say it's a little misleading to say it's a "little bit of both." The vast majority of the park's collection is accessible only by trams/buses (or a few upcharge experiences. including zip-lines and horseback safaris), and to reach either the carnivore complex (home to cheetah, painted dog, and dhole) or the lake trail (mostly scenic, with the budgie exhibit and the goral exhibit) you must take a tram. I highly recommend anyone visiting the Wilds take binoculars, which can really help seeing many of the species, which can keep a large distance from the tram route.