One of Madrid's oldest museums, dating back to 1867, this shares the same building as the Biblioteca Nacional and Museo del Libro. It traces the evolution of human cultures, from prehistoric times up to the 15th century, and the collection of artefacts includes finds from the Iberian, Celtic, Greek, Egyptian, Punic, Roman, Paleochristian, Visigothic and Muslim cultures. Remarkably, the great majority of pieces came from excavations carried out within Spain, illustrating the extraordinary continuity and diversity of human settlement in the Iberian peninsula. To tour the whole museum in chronological order, begin in the basement, which holds palaeontological material such as skulls, tombs and a mammoth's tusks, still attached to its skull. Some of the most interesting relics are from the area around Madrid itself, such as the many 4,000-year-old neolithic bell-shaped pottery bowls. The first floor holds the museum's most famous possession, the Dama de Elche, the intricate stone bust of an Iberian priestess, believed to date from 500BC. Further up, the usual definition of archaeology is stretched to include interesting exhibitions on post-Roman Visigothic and Muslim Spain, with wonderful ceramics and fine metalwork from Moorish Andalucia. After that there is a whole series of rooms dedicated to pieces from the Middle Ages and later eras. In the garden, steps lead underground to a reproduction of the renowned Altamira prehistoric cave paintings in Cantabria.