'The fastest speed ever traveled by human beings is nearly 25,000 miles per hour.'
Apollo 10, which was essentially a practice run for the Apollo 11 moon landing, returned to Earth on May 26th, 1969. During reentry, the command module hit a velocity of 24,791 miles per hour (39,897 km/h), according to Guinness World Records. The Apollo 10 mission report's own estimate is actually slightly faster (24,816 mph).