The Small Intestine Is About 6–7 Metres Long and Has the Surface Area of a Tennis Court
Despite being called 'small', the small intestine is the longest section of the digestive tract, measuring 6–7 metres in adults. Its inner surface is covered with millions of finger-like projections called villi, and each villus is covered with even smaller microvilli (the 'brush border'), which together increase the total absorptive surface area to approximately 250–300 square metres — roughly the size of a tennis court. Food takes 2–6 hours to pass through.