The average person swims at a speed rarely exceeding two miles per hour, or 3.2 km/h. A fit, young, and fully trained Olympic swimmer fares much better, with speeds of up to five mph (8 km/h) not uncommon. But this is a snail's pace compared with the velocity some marine animals can achieve. And you won't believe the acceleration rate the very fastest are capable of!
Curious? Click through this gallery and read about the swiftest species in the ocean—and discover the speediest of them all.