The Tokaido and Nakasendo are representative highways of early modern Japan. Both highways served to connect Edo and Kyoto, two of Japan's leading cities at the time, on the sea side and the mountain side, respectively. However, due to the steep topography of the Japanese archipelago and the large difference in elevation, these roads have not been used much since modern times. As a result, many remains from that time remain along both highways.

Most of the Tokaido and Nakasendo roads are made up of roads that pass through plains and mountainous areas. In particular, in the mountainous areas, there were many places where stone pavement was laid to prevent slipping even in rainy weather. Also, for defensive reasons, places were deliberately built where people could cross rivers and the sea by boat.

In addition, rows of pine trees planted along the road provided shade and served as guideposts, and ichiri-duka (mileposts) were set up every ri (approximately 4 km) to indicate the distance from Edo.

Many post towns were established along the roads, and served as bases for people traveling along the Tokaido and Nakasendo roads. Post towns were primarily equipped with honjin and wakihonjin inns where feudal lords and others stayed, Hatago (traveler's lodgings) where people of lower status could stay, and Post station office (Toiyaba) which were responsible for maintaining public order in the post towns. A notable feature of the Nakasendo road, which runs along the mountain side, is that it avoided excessive development and was built in harmony with nature.

It was the Edo Shogunate that developed the Tokaido and Nakasendo roads. The Edo Shogunate implemented the sankin-kotai system, making these two important routes highly valued for feudal lord processions. The Tokaido and Nakasendo roads also vividly convey the political system of the Edo period. Both roads were also taken by envoys from countries that had diplomatic relations with the Edo Shogunate, and their footsteps can be seen along the roads. Examples include the Korean envoys (Chōsen Tsūshin-shi) and the Ryukyu envoys.

The shogunate believed that allowing anyone to travel freely would pose safety problems, so they set up two large checkpoints on each of the two roads.

In addition to the checkpoints, huge castles were built along the roads as defenses to keep local daimyo in check.

The Tokaido and Nakasendo roads are also deeply connected to the political system of the time.

The economy also developed significantly, targeting the many people traveling between the Kaido and Nakasendo roads. Many merchants were built along the roads, selling goods and providing directions to people traveling along the roads. Other major developments included local specialties and regional industries. In some cases, regional industries became town-wide industries, bringing prosperity to the towns.

There are also many other literary works and ukiyo-e prints that feature the highway as their subject.

The Tokaido and Nakasendo are inseparable when talking about Japan in the Edo period.

The above information can be summarized in the following figure:

The Tokaido and Nakasendo roads, and the cultural assets that remain along them, are truly amazing. They are truly cultural assets that we can be proud of around the world!

There are ninety-four in total.