Can you tell me what the 'Grand National' is?

The Grand National is a famous steeplechase horse race held annually at Aintree Racecourse near Liverpool. Steeplechases are horse races where competitors jump over obstacles. The Grand National is known for its challenging course, featuring large fences like Becher's Brook and The Chair, which test the skill and endurance of both horse and rider. The race has a long history, dating back to 1839, and has become a significant part of British sporting culture. It attracts a huge audience, both at the racecourse and on television, and is a major event in the horse racing calendar. While the other options – tennis, football, and motor racing – are popular sports in the UK, the Grand National is specifically and uniquely a horse race. The phrase "And they're off!" is commonly associated with the start of horse races, making it a helpful hint.