Humans have been living in the area for between 4,000 and 6,000 years, with the oldest settlements in the southern part. In the pre-Hispanic period the area was important for its commercial routes which linked the Gulf Coast, the Huasteca Region and the central highlands of Mexico principally, but there is evidence of commercial traffic from much further away. This made the area one of cultural exchanges with various ethnicities. When the Spanish arrived, the area was inhabited by the Chichimeca Jonaz, the Huastecas, the Ximpeces and the Pames.(arqueomex) Four archeological sites are open to the public: Las Ranas, Toluquilla, El Quirambal and El Cerrito.