Pony Penning is an annual event held in Chincoteague, Virginia on the last consecutive Wednesday and Thursday in July. The Chincoteague Volunteer Fire Department conducts the event and it consists of a Wild Pony Swim on Wednesday and a Pony Auction on Thursday. For the Wild Pony Swim, Salt Water Cowboys round up feral Chincoteague Ponies from Assateague Island and drive them across the Assateague Channel to Veteran's Memorial Park on Chincoteague Island. The ponies swim across the channel during slack tide, when the water has minimal tidal movement. Once on Chincoteague Island, the salt water cowboys herd the ponies to pens on the Chincoteague Carnival Grounds where some of the foals are auctioned off on Thursday.
This traditional event in its current form has taken place since 1925 to raise money for the Chincoteague Volunteer Fire Department, but its roots date back to the 17th century. The event was popularized by the book Misty of Chincoteague by Marguerite Henry, published in 1947. It now usually draws from 40,000 to 50,000 spectators.