PL Mercury broke his own record as the oldest horse to complete the 100-mile Tevis Cup endurance ride last weekend at the age of 27.5 years. Here, he navigates the 2018 trail with owner Claire Godwin, DVM. | Photo: Bill Gore/Courtesy Marsha Hayes

When Claire Godwin, DVM, of Laytonsville, Maryland, responded to an ad in a local horse magazine offering an Arabian for sale some years ago, she thought she was buying a 4-H pony for her kids. She had no idea that the 14-hand gray gelding would eventually carry her and more than a dozen other riders down some of the toughest endurance trails in the U.S.

On Saturday, Godwin and that gelding PL Mercury, now 27.5-year-old, crossed the finish line at the 100-mile Tevis Cup, held annually in California. With this completion, “Merc” broke his own record as the oldest equine Tevis Cup finisher.

What’s more, the pair finished just outside the Top 10 in 13th place from a field of 149 starters, of which only 64 completed. Their ride time of 17 hours, 18 minutes was just two hours, 33 minutes behind the winners, Heather Reynolds and the 10-year-old Arabian gelding Cayucos