What really makes Thunderdash different is an all natural environment on a beautiful private property in the Texas Hill Country! The natural obstacles on this course are incredible and the mud comes from natural springs on and around the course. There isn’t a course like this anywhere else in the world! Race options include a 10K Combo Challenge & 5K Obstacle Course and 5K Fitness Challenge. 15% off for SARR members, just use promo code SARR15 when registering.