The wild horses who live on Assateague Island in Maryland made the journey to Chincoteague, Va. yesterday as part of the annual pony swim.

For the 88th year, the ponies were herded across the Assateague Channel so some of them could be auctioned off to benefit the Chincoteague Volunteer Fire Company. In what may be a first, the approximately 150 ponies had to battle a heavy downpour as they made the five-minute swim, the Chincoteague Beacon reported.

Today, 53 foals will be put up for auction. Ponies donated back or not sold return to Assateague to enjoy another year of being gawked at by visitors.

Interest in the event reached new heights after the publication of Marguerite Henry’s 1947 book Misty of Chincoteague, which was adapted for a 1961 film. The real Misty, who died in 1972, and her colt Stormy were preserved through taxidermy and are on display at the Museum of Chincoteague.