The Brimhaven Agility Arena is a training area in the game Old School RuneScape designed for players to improve their Agility skill. Located on the island of Brimhaven, it features various agility obstacles that players can navigate to gain experience points. Players can access the arena by paying a small fee to a nearby NPC. The arena offers a unique training experience, allowing players to complete courses that are more efficient than traditional methods. Additionally, the arena includes a reward system, where players can earn tickets to exchange for various items.