The Arbre du Ténéré was the loneliest tree in the world. It stood on a caravan route in the Ténéré region of Niger, in the dune seas of the Sahara. Arbre du Ténéré, in the company of some other little Acacia trees, took root there a long time earlier, when the ground was not quite so dry. After things dried up and his colleagues dwindled away, Arbre du Ténéré stuck around—his roots stretching 131 feet into the soil and his isolation stretching 120 miles in all directions.

Michel Lesourd described the tree in 1939:

One must see the Tree to believe its existence. What is its secret? How can it still be living in spite of the multitudes of camels which trample at its sides. How at each azalai does not a lost camel eat its leaves and thorns? Why don't the numerous Touareg leading the salt caravans cut its branches to make fires to brew their tea? The only answer is that the tree is taboo and considered as such by the caravaniers.

There is a kind of superstition, a tribal order which is always respected. Each year the azalai gather round the Tree before facing the crossing of the Ténéré. The Acacia has become a living lighthouse; it is the first or the last landmark for the azalai leaving Agadez for Bilma, or returning.

Thirty-odd years later, the Arbre du Ténéré's loneliness was abruptly ended:

The tree was knocked down by an allegedly drunk Libyan truck driver in 1973.

(List of famous trees is occupying my brain today.)