There is an old brick tunnel was constructed about 100 years ago.
Matsuo Basho
While writing his famous travelogue Oku no Hosomichi, The Narrow Road to the Interior, renowned 17th-century poet Matsuo Basho made the journey through Oyashirazu and stayed at an inn called Kikyo-ya in Ichiburi. At the inn, he wrote about the perilous crossing and penned a now-famous haiku: Hitsuya ni Yuujo mo netari Hagi to tsuki(Under the same roof, Prostitutes also sleep, Clover and the moon.).