The 51st annual 'Buffalo Roundup' has taken place at Custer State Park in the US state of South Dakota.
Every year up to 14,000 people visit the park to watch over 1,000 buffaloes being sorted, counted and vaccinated.
Witnesses sat on a hill at a safe distance to watch as the cattle ran along the plains, shaking the ground. Pick up trucks joined the cowboys on horseback to help guide the buffalo in the right direction.
Organizers say the roundup was not always public as it is today, but it has evolved into an internationally known event.