Arai is Japan’s only surviving feudal era checkpoint. Nestled on the west bank of Lake Hamana in modern day Shizuoka Prefecture, in feudal times access eastwards (to and from the capital Edo, modern Tokyo) was only by boat. Bridges were prohibited by the Shogun to make it difficult for any would-be upstart from the provinces to lead an army in rebellion against the capital. The checkpoint was re-located a short distance twice during the 18th century to more sheltered spots as Japan’s famous typhoons took their toll.

Lake Hamana itself has an interesting history. Today it is known as the “sea-lake” as it has a narrow opening into the Pacific Ocean, allowing salt-water to mix with the fresh lake water to create a unique brackish ecosystem, home to rich local fishing resources. This hasn’t long been the case though. Five centuries ago Hamana was a true, fully enclosed lake, but an earthquake in 1498 collapsed the narrow bank separating the lake from the ocean.
This natural development created an ideal harbor, and today you can see many small fishing and pleasure vessels on the lake powered by throaty Yamaha outboards. This Hamamatsu/Hamana area is the global home of Yamaha. In the 19C, Mr Yamaha, a piano tuner living in Tokyo, was commissioned to journey out to Hamamatsu to tune a wealthy patron’s piano. Yamaha walked the Old Tokaido Highway 220kms from Tokyo, and after completing his immediate assignment decided to stay in the area because of its beauty and potential. Yamaha decided to venture into manufacture, and the rest is history. The area is also the origin of other world-famous brands including Suzuki, Honda, and Toyota.

You can see a delightful recreation at Arai Checkpoint of the facility used in feudal times to check the gender of travelers along Old Tokaido foot highway. The paranoid Shogun kept many female hostages in the capital, Edo (modern Tokyo). These were the wives/daughters and other close relatives of provincial Lords, supplied to the capital under duress from throughout the land as a disincentive to their attempting coups d’etat. Of course, this deterrent system only worked if the hostages were unable to escape the capital disguised as men.
You can enjoy a day-return from Tokyo walking or hiking tour of Old Tokaido Highway.