How did pony's first get to assateague island?

Legend has it that a Spanish ship carrying horses crashed close to shore. The horses that survived then swam to Assateague island. You can read about this legend in "Misty of Chincoteague."

It wasn't just a shipwreck, when they looked into the ponies ancestors they found many different kinds of horses so in the beginning the researchers thought that farmers took horses to Assateague to avoid taxes on the horses. It was a natural corral. Over time they adapted to the climate and other horses ended up on the island, they may have come from a ship or swam from mainland. There are hundreds of stories how the ponies got there but they are there and thriving.