Japan is roughly seventy percent mountainous. Post-war road engineers cut narrow S-bend roads through the passes for commercial trucks. From the 1960s and 1970s onward, those same bends became the playground of an underground driving culture, and by the 1980s and 1990s the practice had crystallised into the hashiriya (走り屋, "speed tribe") subculture. The discipline is distinct from circuit racing: closed environment versus public road, organised event versus secret meet, sanctioned versus illicit.
Touge driving runs in three core formats. Solo time-attack — touge attack — pits the driver against the clock and the mountain. Tsuiso, also written tsuiou (追走バトル, "chasing battle"), is the canonical leader-follower format: two cars nose-to-tail, leader tries to escape, chaser tries to close to bumper contact, then the pair swaps and the result is decided on combined gap delta. Battle, or tatakai, is the generic 1v1 confrontation label.
Direction matters. Downhill touge (kudari) rewards braking discipline, weight transfer, and bravery — Takumi Fujiwara's specialty in Initial D. Uphill (nobori) is a power-and-grip contest. The canonical gutter-running technique — putting the inside tire into the concrete drainage gutter on a hairpin to tighten radius — is the trademark Akina and Haruna trick portrayed in Initial D.
Touge culture runs on an unwritten code more honoured than traffic law: location never published, groups stay small, no crossing the centre line, lookouts at top and bottom, accept that someone is always faster, contact tolerated as incidental but punished as aggression. The code is the diagnostic line between touge and bosozoku — touge demands secrecy, bosozoku demand spectacle.
The two geographic centres of the Kanto scene are Gunma — home to Mt. Haruna (the real-world Akina), Mt. Akagi, and Usui Pass — and Kanagawa, home to Hakone Turnpike, Yabitsu Pass, and Nagao Pass. Tochigi contributes Irohazaka with its 48 named hairpins. Saitama contributes the closed private Gunsai Touge, the "mini Nürburgring" where Best Motoring and Hot Version relocated when public-road filming became untenable. Hyogo's Rokko Skyline is the Kansai counterweight. Tsukuba Skyline, the "Purple Line" in Ibaraki, is another Kanto icon. "Gunma plates" still carry mystique in JDM communities worldwide.
Touge's tsuiso format was lifted wholesale into the D1 Grand Prix when Inada and Tsuchiya formalised the bracket-elimination tandem battle in 2001, and from D1GP into Formula Drift when Jim Liaw and Ryan Sage founded the American series in 2004. Touge is the cultural root of the global drift competition format.
Public-road touge is illegal under Japan's Road Traffic Act. Offences applied include reckless driving, speeding, kyodo kiken gata bouso (group street racing), and obstruction. Enforcement intensified through the 2000s-2020s via unmarked patrols, cameras, citizen reporting, and drone surveillance. The active hashiriya population has shrunk substantially. The displaced energy moved to track-day touge at Ebisu Circuit South Course (de-facto global drift Mecca), Bihoku Highland, Nikko Circuit, and closed Gunsai. Hakone Turnpike has been formalised as the legal sponsored Anest Iwata Turnpike.
Forza Horizon 6 ships a dedicated Touge Battle mode — new to the series — running head-to-head down twisting passes at night, with emphasis on launch, track position, and defence over top speed. Five official Touge Battle routes anchor the system: Mt. Haruna (the Initial D Akina), Hakone Nanamagari, Bandai Azuma, Norikura Skyline, and Arahiyama Takao Parkway. Mt. Fuji is in-world but is not a touge battle node. Touge is the central driving register the game is built around.