The trees were planted over a period of 20 years beginning in 1625 as an approach to Nikko’s Toshogu Shrine by Matsudaira Masatsuna, a feudal lord serving Tokugawa Ieyasu. After Tokugawa Ieyasu death in 1616, Masatsuna Matsudaira undertook the construction of Nikko Toshogu shrine, and he began to plant Japanese cedar trees along the main roads leading to Nikko. It is estimated that some 200,000 cedars were planted on this occasion. Large-scale felling for road construction and the relentless exposure to vehicle exhaust has damaged the trees reducing their numbers to just 13,000 today.
Back in the Edo Period, the Cedar Avenue used to be under the control of the Nikko Bugyo (Magistrate), and was well cared for. Whenever withered or uprooted cedar trees were discovered, village officials were obliged to notify the magistrate's office. Damaged trees could only be felled after it was permitted by the officer of the Magistrate, and it was mandatory to plant seedlings in the empty plots of land where the trees had been removed. At the same time, the villages along the road were responsible for road repair, weeding, and for keeping the entire Cedar Avenue clean, and so forth.
With the modernization policies of the Meiji Government, civil engineering work came to be carried out nationwide. During this period, thousands of trees were felled for road maintenance. Furthermore, plans were drawn up to implement the full-scale logging of the Cedar Avenue for the purpose of financial reconstruction, but this was fortunately evaded.
Today, the Cedar Avenue of Nikkō is a cultural property and the only one designated by the Japanese Government as both a Special Historic Site and a Special Natural Monument.
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