The CENIEH archaeopalaeontological collection comprises pieces from the Sierra de Atapuerca sites on temporary deposit, as provided for in the Agreement signed between the CENIEH, the Consejería de Cultura y Turismo of the Junta de Castilla y León and the Fundación Siglo para el Turismo y las Artes de Castilla y León. These pieces include human fossils, fauna and lithic pieces from Pleistocene levels of the Galería, Gran Dolina, Trinchera Penal, Sima del Elefante, Cueva Fantasma and Sima de los Huesos sites.
The collection expands each year as new pieces are deposited in accordance with a calendar established in advance. These items must be inventoried and cataloged following deposit. The enormous number of these pieces and how long these operations take normally means there is a delay of one year between the date of deposit and the moment of availability to the scientific community for consultation. The items currently inventoried and available for consultation are detailed in the document "Inventoried items".