I remember decades ago when reading schoolbooks a "fact" often given- if all the blood vessels in a person were laid end to end they would be thousands of miles long- it was usually "to the moon and back" or circle the equator 4 times. In other words about 60,000 miles at the least. I read this again recently and it got me wondering. This has always seemed incredible to me. Not only incredible as in amazing, but literally "in-credible" as in not believable. There is literally 4 times around the equator lying within my 6 foot body? Is it true, or just another myth that gets perpetuated through the years? I i know some supposed science facts are just not true- sinks don't drain in opposite directions in the northern and southern Hemispheres, and celery does not have negative calories. Even in music there is a myth that gets perpetuated even by music teachers, that the "tritone" was banned in medieval times. It's just not true yet even highly regarded music scholars are guilty of spreading this myth. Science can be amazing, and I'm prepared to be amazed and apologize for my scepticism, but....60,000 miles of blood vessels?