Whether you play or watch, it’s a guarantee that you’ve never experienced anything like Goalball. Goalball features two teams of three players attempting to roll or throw a ball implanted with bells into the other team’s goal. All players are fitted with blindfolds and use the sound of the ball to determine the direction it travels. Officially, the Paralympic sport is exclusive to athletes with visual impairments.

Developed in 1946, Goalball was originally intended as a rehabilitation exercise for war veterans who had lost their sight. It took about 30 years for the exercise to develop into a competitive sport and in 1980, Goalball became a part of the Paralympics and has remained ever since.

While Goalball incorporates elements of several sports—from dodge ball to bowling, spectators of the sport are required to adopt “golf gallery” etiquette: Because the sound of the bells inside the ball is so key, silence during play is essential. Teams must have the ability to listen to the sound of the bell to determine the flight of the ball in order to defend their goal, usually by laying in front of the ball’s path.

Goalball will feature 12 men’s teams and 10 women’s teams, with 132 athletes showcasng their skills at the this year’s game. Don’t forget to mark your calendars for August 26 when the games begin.