"The Tortoise and the Hare" is one of Aesop's most well-known fables and it takes for granted the knowledge that a tortoise cannot move quickly, but in the end the tortoise beats the rabbit in a race by patience and perseverance. That means that for at least the last 2,600 years, humans knew that turtles were slow. Recent inquiry has shed light on just how slow they truly are. While the average turtle can only "run" 3 or 4 mph, there are some who are much slower.
Tortoises are land-only turtles who do not swim well, if at all. They, like the tortoise in the fable, are the slowest of the types of turtles listed here. On land, tortoises of the genus Gopherus have been clocked at speeds of 0.13 to 0.3 mph.
Land turtles such as the box turtle are commonly kept as pets and knowing how fast they can go can help you keep on eye on them if you let them out into your garden, for instance. In an experiment, the box turtle has been clocked as fast as 0.25 mph over a short distance, but a more average walking speed is 0.17 mph. A box turtle will rarely cover 100 yards in a full day of walking. The box turtle will close up into its shell to protect itself from predators rather than trying to run away.
A prized pet and normally aquatic turtle from North America, cooter turtles do not travel far from water. Through natural observation, cooter turtles have been recorded walking about 1.07 mph, making them faster than box turtles and tortoises, but still pretty slow. Though they can close up entirely into their shell like the box turtle, they can head for water, where they can swim much faster than they can walk.
While not normally kept as pets, sea turtles generally are recognized as the fastest of the turtles. Even though they can't walk any faster than any other turtle, in the water, they are the fastest swimming reptile on Earth, reaching up to 20 mph.