Archaeologists unearthed eighteen roots of willow trees from the late 10th century in the Aoyayokogi ruins, Tottori, Japan. The alignment of the roots in intervals of 0.5 to 2 meters along a 60-meter stretch provides evidence to an existence of an ancient boulevard, purpously lined with trees.
That stretch is believed to have been part of Sanindo, one of the national roads managed by the state, that was constructed from the late Asuka Period (592-710 AD) to the early Nara Period (710-784 AD). According to archaeologists, poplar trees were normally planted in the ancient capital, and finding them in such a rural area was a surprise. It seems that the ancient state aimed at dramatic visual effects to show off its authority by setting up the same boulevard trees as in the capital. About 40 stakes, including ones made of chestnut wood, were also uncovered in an area stretching about 100 meters. The stakes were likely splints that supported the willow trees. Radiocarbon dating provided evidence that the tree roots and stakes on the outer side of the road site came from the late ninth century to late 10th century.
(after Asahi Shimbun & Tottori Prefectural Archaeological Center)