We can't create Jurassic Park era (yet) but there is a place on Earth lost to time, a modern proxy of the Pleistocene (35,000 to 12,000 years ago). Other than the mammoth and a few other species, the flora and fauna remain largely unchanged, even the climate is similar to the last ice age (cold and dry). There are wild horses, reindeer, saiga antelopes, argali sheep, wolverines and snow leopards. The Altai and Sayan mountains of western Mongolia and southern Russia (map)... [more inside]
Why no Pliestocene Park? "Everyone seems to assume that the primeval condition of the Great Plains was bison and prairie dog, with the occasional pronghorn herd, but no other large mammals. Yet for 1.65 million years, North America teemed with large animals: the 'pleistocene megafauna.' Then as the last ice age was ending and the first humans were coming over from Siberia, most of them died out." Sad -- doesn't everybody want a pony?