The Medina Azahara was 2000 metres long and 900 metres wide. It climbs down to the Guadalquivir river by 3 terraces. In order to entertain az-Zahra, a zoo, an aviary, 4 large fish ponds and 300 baths were added to the palace. The employees of the palace filled 400 houses,and there were weapons factories and several mosques as well. The wealth of the area was stunning to contemporary visitors. Many of the public rooms were decorated with visual effects. One conference room had crystals creating an inner rainbow when lit by the sun. Another room had a mercury bowl in its centre, that would send sunbeams around the room if rocked. The life span of the Medina Azahara was short, less than 100 years. Its demise would not come from abandonment, rather it became virtually a prison for the caliph. With the vizier al-Mansur in Cordoba and the caliph in Medina Azahara, control moved from the caliph, and Medina Azahara was unable to protect itself from a mob in 1010, and was subsequently burned.