If you're old enough, you just might remember Misty of Chincoteague, the story by Marguerite Henry about the wild horses of Assateague Island.
Here's the backstory from the National Park Service:
Assateague's wild horses are well known, even to many people who have never been to the island. The "wild" horses on Assateague are actually feral animals, meaning that they are descendants of domestic animals that have reverted to a wild state. Horses tough enough to survive the scorching heat, abundant mosquitoes, stormy weather and poor quality food found on this remote, windswept barrier island have formed a unique wild horse society. Enjoy their beauty from a distance, and you can help make sure these extraordinary wild horses will continue to thrive on Assateague Island.
Local folklore describes the Assateague horses as survivors of a shipwreck off the Virginia coast. While this dramatic tale of struggle and survival is popular, there are no records yet that confirm it. The most plausible explanation is that they are the descendants of horses that were brought to barrier islands like Assateague in the late 17th century by mainland owners to avoid fencing laws and taxation of livestock.
Been to Assateague many times and camped there. The mosquitoes are very bad. The horses are very friendly they check out campgrounds and steal food regularly. The come up to be petted and do not bite and kick, unlike thouroughbreds. These horse are extremely good natured. They have patterns like at 5 pm they go to the beaches and if they find food. Chips in bags they go from being carelful not to step on towels to a rush and then kick and squeal amoung themselves in a pecking order on who get the goodies. It is highly amusing to watch the people get stuck in the waves by the herd taking over the beach. Until the herd has left.
Being an expert horseman I had no problem, a slap and yell will turn the horse away from you with no harm to either.
But the horses are beautiful.