Radiometric dating, often potassium-argon dating, of deposits containing Acheulean material is able to broadly place Acheulean techniques from around 1.65 million years ago to about 100,000 years ago. The earliest accepted examples of the type, at 1.65 m years old, come from the West Turkana region of Kenya. Some think their origin might be as early as 1.8 million years ago.