The Przewalski wild horse, closest cousin of the domesticated horse could never be domesticated successfully, and so it remained a true wild horse.
The Przewalski wild horse (Equus ferus przewalski) is also known as the Dzungarian horse, or takhi. The closest feral cousins of domestic horses could never be domesticated successfully, so they remained a true wild horse. The species was named for a Russian general, Nikolai Przewalski, who was the first to describe the species to natural science in 1881.
Their meat and hide were both valuable and they were hunted to extinction in Mongolia by the 1960s. At the time, there were just a few individuals left alive in two zoos, in Munich and Prague. The zoos started a breeding program with their stock in 1977, aiming to preserve the species and reintroduce it to its original habitat. As a result, 12 horses were released in Mongolia in 1992 with the help of WWF. Since then, their number has grown steadily, if slowly, so the Mongolian wild horse no longer appears on the IUCN Red List with "extinct in the wild" status, but is listed under the "endangered" species category.
The Przewalski wild horse is stockier than its domesticated cousins and their legs are shorter too. Its height is usually 1.3 m, length 2.1 m, and their tail is 90 cm long. The colour of its coat is similar to domestic horses' greyish-brown colour, dark brown around the mane, and yellowish-white under the belly. Their legs are often faintly striped.
In the wild, these horses live in groups comprised of a dominant stallion, a few mares and their foals. Groups maintain territories where the herd can cover up to 5-10 km a day while grazing, drinking, bathing in mud and sleeping.
The world's largest breeding program was started in Askaina Nova (Ukraine), but research is also being conducted about the characteristics of wild horse populations in Hortobágy National Park, Hungary. So you need not travel all the way to Mongolia to see Przewalski wild horses, it is enough to visit the Hortobágy, where they can be found among semi-wild conditions in the national park.