The late morning light cuts cleanly, throwing sharp shadows across the road as we depart the onsen town of Yufuin. From the valley’s western edge, Prefectural Road 216 winds outward in a single lane, its path lined with moss-darkened stone and swaying silver grass. Before long, it joins a feeder road, where green-and-white expressway signs announce Japan’s national network.

A canopy of steel and LED boards stretches across the lanes ahead. Cash-paying drivers peel off to the right into the ippan lane, while ETC, Electronic Toll Collection, traffic flows left. Our rental carries an ETC tag, a small device linked to a prepaid card, and we move into the left-hand lane. The barriers remain down until the vehicle draws close, when an electronic chirp signals the reader’s handshake with the card. The arm rises at the last moment and we whistle through.

Past the gate, the road merges into the Ōita Expressway. In an instant, Yufuin’s winding lanes are gone, replaced by the engineered mass of the highway. Traffic noise settles into a constant hum. I tap shuffle, and the strings of Sachiko Kobayashi’s rendition of Michizure ring out. The enka classic, its title meaning “travelling companion”, makes a fitting soundtrack for the long green arc ahead.