2013 Grand National to modifications made for the previous year's race, Aintree announced that a number of further changes had been made for the 2013 National. Twelve of the 16 fences on the course were rebuilt with the timber frames within them replaced by a softer material known as "plastic birch". The fences are still covered with at least 14 inches of spruce and will remain the same height. The starting line was also moved 90 yards closer to the first fence, further away from the spectators' stands and thereby reducing slightly the overall distance. Aintree and the Professional Jockeys' Association jointly issued
1849 Grand National the third fence on the second circuit, which resulted in several competitors being knocked out of the race. The custom among riders at the time would have been to continue in the race unless impossible to do so, regardless of how many times they had met with mishap. Therefore, many of the competitors would have been remounted once or more during the race, or put to fences again after refusing. Only those horses that had been injured, run loose after falling, persistently refused an obstacle or had riders too injured or fatigued to continue would not have completed the course.