There are so many blood vessels in your body that if you laid them down end to end, they would wrap around the Earth twice! They would cover a distance of more than 50 thousand miles.
Most of the blood vessels in our bodies are microscopic capillaries. Not only are they short in length, but they appear in vast numbers. The estimated number is around 40 billion. In order to appreciate this interesting human body fact properly, you have to try and understand how much 40 billion actually is. Your heart beats around 100 thousand times a day and at this rate, it would take it 30 years to beat a billion times.