of palaces and pavilions belonging to Artaxerxes. This included gardens watered by an aqueduct – the earliest known record of gravity-fed water rills and basins arranged in a geometric system. The Spartan General Lysander who joined Cyrus as a mercenary reported to Xenophon how Persian kings "excelled in not only in war but also in gardening, creating paradeisos" where they collected plants, especially fruit-bearing trees and animals encountered during foreign campaigns. The four-fold layout was later reinterpreted in Islamic terms by Muslim Arabs after the 7th-century conquest of Persia, becoming associated with the Abrahamic concept of paradise and the Garden of Eden. Genesis 2:10 reads, "And a river went out of Eden to water the garden; and from thence it was parted, and became into four heads." and the Prophet Muhammad spoke of four rivers: of water, milk, wine and honey. By the 13th century the gardens had spread with Islam throughout Egypt, Mediterranean north Africa and into Spain. This style of garden came into India during the 16th century in the reign of Prince Babur, the first Emperor of the Mughal Empire. Most Mughal gardens came to have a tomb or pavilion in the centre, the most famous of which is the Taj Mahal although with the decline of the Mughal Empire and British colonial rule, the original garden has been substantially changed. Features The essential plan of a paradise garden is a four-fold layout (charbagh) with a pond or fountain in the centre. Later designs incorporated a pavilion or mausoleum when they began to develop into elaborate status symbols. The rectangular or rectilinear design is typically quartered by water channels made using the ancient qanat system. An important and common feature is the elaborate use of water, often in canals, ponds, or rills, sometimes in fountains, and less often in waterfalls. This created the soothing sound of running water and also had the practical purpose of cooling the air. Aromatic flowers and fruit-bearing trees are quintessential elements. The ground where the flora were planted was sunken or the walkways raised so that passers-by would be able to easily pluck fresh fruit as they walked throughout the garden. Olive, fig, date and pomegranate were ubiquitous and symbolically important. Orange trees arrived from India via the Silk Road by the 11th century and were incorporated for their fragrance and the beauty of their flowers. They are typically enclosed by high