In stark contrast to many of today's passport-toting Japanese, their compatriots of old weren't a well-traveled bunch.
During the Edo Period (1603-1867), the feudal government was keen to keep its populace in check, and travel by ordinary citizens was tightly regulated. To this end, the ruling Tokugawa Shogunate established and administered the Gokaido (Five Highways) which crossed central Japan and converged on Edo (present-day Tokyo), so as to keep a close check on who exactly was going where. Among these highways was the Nakasendo.
Unlike the well-traveled Tokaido (Eastern Sea Road), which followed a largely coastal route of some 500 km from Edo to Kyoto, the longer Nakasendo (Middle of the Mountains Road) pursued an inland course between the two cities and bore much less traffic.