【How-to】Why are turtles slow - Howto.org

In an aquatic environment, aquatic turtles (including freshwater turtles, terrapins, and marine turtles) are quick agile. Equipped with flippers or webbed toes, these clumsy creatures that are slow on land become quick in an aquatic environment reaching speeds of 10 knots, which is about 12 miles per hour.