 Early hunter-gatherers who arrived in the region at the end of the third glaciation evolved to become sedentary groups of farmers, complex societies and cultures which formed part of other civilizations.The plentiful natural resources, consequence of the rugged geography formed from millions of years ago, attracted to the Tejupilco region early settlers at least 10 thousand years ago, date in which hunter-gatherer groups created the cave paintings at the "Cueva de los Monitos"; located north of "Bejucos" at the foot of the Nanchititla Sierra.The hunter-gatherer groups have evolved to sedentary tribes through peaceful or violent exchanges with other cultures, to the domain of agriculture and domestication of animals, basic astronomical, medical and scientific knowledge.