The Tree of Life, Shajarat al-Hayat, is a single tree standing alone in the bare desert of southern Bahrain, near the oil fields of Jebel Dukhan, for roughly four hundred years, and its taproot is thought to reach some fifty metres down to a water source that nothing else can find, which is the puzzle that draws the visitors. It is a mesquite, Prosopis cineraria, ten metres tall with a spreading crown of small green leaves, evergreen and looking the same in every season, and the name is not botanical but a story: some say it marks the site of the Garden of Eden, others that Enki, the Sumerian god of water, protects it, since Bahrain was Dilmun, the paradise of the Mesopotamian myths. The tree stands on a low mound that is not just sand but a village, and archaeologists digging beside it in 2010 found pottery and everyday objects from a settlement of the fifteenth and sixteenth centuries, shown in the small visitor centre a few steps away, so the tree may have been planted at a well that the village used and outlived it.
A perimeter wall now keeps the visitors off the trunk, and from it the scars of four centuries and too many people are read, names gouged into the bark, holes worn at the base, limbs cracked and sagging. Walking a few hundred metres off, it shrinks to a single green mark on an empty pan with the people at its base reduced to dots, which is the way to see what it is. The tour buses come in the afternoon, and the site empties toward dusk, when the light goes gold on the desert and the tree stands alone again; from November to March the desert days are mild, and in summer the site passes 40 degrees with no shade but the tree's. The Tree of Life is a tree that should not be there, and nobody has found what it drinks.