The Yonaguni horse — a small, stocky pony breed native to the island — roams semi-wild on the grasslands of the island's northern and eastern coasts. The breed is one of the oldest in Japan and has been on the island for at least 2,000 years, possibly brought by early settlers from continental Asia. The horses are compact and sturdy, adapted to the island's terrain and typhoon-swept conditions, and are designated a protected natural monument by the Japanese government.
The best places to see them are on the eastern grasslands near the East Cape (Agarizaki), where small groups of ponies graze close to the coastal road and are often approachable. Do not feed them or try to ride the wild ones — the herds are managed loosely and the horses are skittish around strangers. A small equestrian centre on the island offers paid rides on domestic animals of the same breed if you want a closer interaction.