During the Edo period, the Tokugawa shogunate maintained a system of highways across Japan, including the Edo Five Routes, which connected the Shōgun's capital of Edo with the provinces. These routes were marked with ichirizuka to indicate distance, and were planted with trees on either side (typically Japanese red pine or cryptomeria) to provide shade for travelers. The routes to Nikkō were of especial importance to the Shogunate, as it held the mausoleum and memorial shrines and temples to its founder, Tokugawa Ieyasu, and his grandson Tokugawa Iemitsu, and was thus a pilgrimage destination for generations of Shōgun and important daimyō.
The project to plant the approaches to Nikkō with cryptomeria was begun by Matsudaira Masatsuna, daimyō of Tamanawa Domain in Sagami Province, and a descendant of a cadet branch of the Matsudaira clan. He began donating and planting seedlings brought from Kii Province around the year 1625. The cedar-lined approaches were officially dedicated to Tokugawa Ieyasu in 1648, on his 33rd memorial anniversary, and Matsudaira Masatsuna died later the same year. Memorial stone markers were erected in four locations by his son, who continued the project and, together with later donations, it is estimated that some 200,000 trees were planted. During the Edo period, the trees were managed by the Nikkō bugyō, the magistrate in charge of the Nikkō shrines and temples. After the Meiji Restoration, the trees were endangered by neglect and logging, but an estimated 12,500 trees survive to this day.
These 400-year-old trees remained endangered due to continued urban encroachment and due to the exhaust from automobiles, as the former footpaths they line have become modern highways (Japan National Route 119 and Japan National Route 121).
