Forty-eight hairpin turns. Two one-way roads. Each corner named after a character from a thousand-year-old Japanese poem.

Irohazaka isn't just a driving road — it's a piece of living history carved into the mountains of Nikko. The road system connects the town of Nikko with the shores of Lake Chuzenji, climbing nearly 400 meters through some of the most spectacular autumn scenery in Japan. And for driving enthusiasts, it's one of the most unusual and rewarding mountain passes you'll find anywhere.

The short answer: Irohazaka consists of two separate one-way roads — the "First Irohazaka" (downhill, 28 turns) and the "Second Irohazaka" (uphill, 20 turns). Together they have 48 hairpin turns, each marked with a character from the classical Japanese iroha poem. The uphill road (Second Irohazaka) is the newer, wider route used for ascent. The downhill (First Irohazaka) is narrower and more technical. Both are free, open year-round, and located in Tochigi Prefecture about 2.5 hours north of Tokyo.

Table of Contents

What Is Irohazaka?

Irohazaka (いろは坂) is a pair of mountain roads in Nikko, Tochigi Prefecture, connecting the town of Nikko with the Lake Chuzenji area higher up the mountain. The name comes from the iroha — an ancient Japanese poem that uses each character of the classical Japanese syllabary exactly once, similar to a pangram in English.

The original Irohazaka road was built in the early 20th century as a single two-way road with 28 hairpin turns. As traffic increased (particularly tourist buses heading to Lake Chuzenji and the Kegon Falls), a second road with 20 hairpins was built alongside it. The solution was elegant: the old road became one-way downhill, the new road became one-way uphill, and each of the 48 combined hairpins was assigned a character from the iroha poem.

The result is a mountain pass system unlike anything else in the world. You drive up one road and down another, each with its own character, and every single hairpin has a name.

Irohazaka Quick Reference

Detail Info
Total hairpins 48 (20 uphill + 28 downhill)
Elevation change ~390 m (from ~600 m to ~1,270 m at Akechi-daira)
Second Irohazaka (up) Route 120, 20 hairpins, wider, modern
First Irohazaka (down) Old road, 28 hairpins, narrower, more technical
Surface Good asphalt, well-maintained
Toll Free
Open Year-round (winter chains/snow tires may be required)
Difficulty Moderate-to-challenging (especially the downhill)
Best season Mid-October for autumn foliage
Best time of day Early morning (before 7 AM) to avoid tourist traffic
Location Nikko, Tochigi Prefecture, ~150 km north of Tokyo

The Iroha Poem and the Hairpins

The iroha (いろは) is a classical Japanese poem dating to around the 10th century. It's remarkable because it uses all 47 characters of the classical Japanese syllabary exactly once (plus one additional character). Think of it as the Japanese equivalent of "The quick brown fox jumps over the lazy dog" — but as a poem with actual philosophical meaning.

The poem reads:

Iro ha nihoheto / Chirinuru wo / Waka yo tare so / Tsune naramu / Uwi no okuyama / Kefu koete / Asaki yume mishi / Wehi mo sesu

Roughly translated: "Colors are fragrant but they scatter. Who in this world is unchanging? The deep mountains of vanity — cross them today, and shallow dreams shall intoxicate no more."

Each hairpin on Irohazaka is marked with a stone pillar bearing one character from the poem, starting from "i" (い) at the bottom. As you drive through all 48 turns, you're literally reading through an ancient poem carved into the mountainside.

It's the kind of detail that makes Japanese road culture unlike anything else.

How to Get There

From Tokyo by car: Take the Tohoku Expressway north to the Utsunomiya IC, then follow the Nikko-Utsunomiya Road toward Nikko. From Nikko, follow Route 120 toward Lake Chuzenji. You'll reach the Second Irohazaka (uphill road) automatically. Total drive time from central Tokyo is approximately 2 to 2.5 hours.

From Nikko station: If you're renting a car locally, major rental agencies operate near both Tobu Nikko and JR Nikko stations. The Irohazaka entrance is about 15 minutes west of Nikko town.

By Shinkansen: Take the Tohoku Shinkansen to Utsunomiya (50 minutes from Tokyo), then transfer to the JR Nikko Line or Tobu Nikko Line. Rent a car at the station.

First Irohazaka: The Downhill (28 Hairpins)

The First Irohazaka is the original road, built in 1954. It's the one-way downhill route from Lake Chuzenji back to Nikko. With 28 hairpins packed into roughly 6 km of road, this is the more technical and more interesting drive.

What to Expect

The road is narrower than the uphill route, with tighter corners and less room for error. Guardrails are present but the road feels more exposed. The hairpins come in rapid succession — you're rarely on a straight section for more than a few seconds before the next turn appears.

The corners vary in radius. Some are standard hairpins with a clear apex. Others tighten unexpectedly or have slightly off-camber exits. On a road with 28 turns in quick succession, these rhythm changes keep you fully engaged.

This is where having corner calls makes a real difference. Twenty-eight hairpins is a lot to process, and the variation between them means you can't just repeat the same input. Rods calls each corner's severity through your speakers — so hairpin 14 that tightens on exit doesn't surprise you the way it would driving blind.

The Character of the Descent

Descending the First Irohazaka is genuinely thrilling. The one-way system means no oncoming traffic, so you can use the full road width. The forest canopy closes in, creating a tunnel effect. Each named hairpin passes with its stone marker, counting down through the poem.

The gradient is steep enough that engine braking is essential — riding the brakes through 28 hairpins will overheat them. Use a low gear and let the engine do the work.

Second Irohazaka: The Uphill (20 Hairpins)

The Second Irohazaka was built in 1965 as a more modern, wider alternative for uphill traffic. It runs parallel to the First Irohazaka but follows a slightly different path up the mountain.

What to Expect

The road is wider, smoother, and more forgiving than the First Irohazaka. The 20 hairpins are more evenly spaced, and the corners have better sightlines. This is the road most tourists experience, as it's the only way up to Lake Chuzenji.

Don't underestimate it though. Twenty hairpins with 390 meters of elevation gain is still a serious climb. The gradient is consistent, and the corners require steady throttle management and clean lines.

Akechi-daira Viewpoint

Near the top of the Second Irohazaka, the Akechi-daira observation deck offers panoramic views of the valley below, the Kegon Falls, and Lake Chuzenji. There's a ropeway (cable car) to an even higher viewpoint. On clear autumn days, the view from here — a sea of red and gold foliage stretching across the mountain — is one of the most photographed scenes in Japan.

It's also a good place to catch your breath after 20 hairpins and reflect on the fact that you still have 28 coming on the way down.

Best Direction and Best Season

Direction: The one-way system means you don't choose — you go up on the Second Irohazaka and down on the First. But this is actually the ideal order. The wider, gentler uphill road lets you warm up, and the tighter, more technical downhill is the reward. The First Irohazaka descent is the highlight.

Best season:

  • Mid-October is the undisputed winner. Irohazaka's autumn foliage is considered among the best in all of Japan. The mountain burns with red maple, golden ginkgo, and orange beech. The contrast against the grey road and dark tree trunks is extraordinary.
  • Late April to May — Cherry blossom season in the lower sections. The mountains are fresh and green.
  • Summer (July-August) — Lush green canopy, comfortable temperatures at altitude, but increased tourist traffic.
  • Winter (December-March) — The road is open but may require snow tires or chains. Beautiful in snow but demanding to drive.

If you visit Japan specifically for driving, time your trip for the second or third week of October. Drive Irohazaka in the morning, then spend the afternoon at Hakone. Two legendary Japanese driving roads in one day.

Irohazaka and Initial D

Irohazaka appears in the Initial D manga and anime as one of the memorable racing venues. The famous scene involves a Nissan Sil-Eighty (Silvia front end on a 180SX body) tackling the downhill hairpins.

For Initial D fans, driving the real Irohazaka is part of the broader Gunma/Tochigi pilgrimage that includes Mount Haruna (Akina) and Tsuchisaka (Akagi). The real road is narrower and less dramatic than the anime portrayal, but the hairpin character is unmistakable.

The iroha poem characters on each hairpin marker are a detail the anime didn't fully capture. Seeing them in person — ancient poetry marking each turn — adds a layer of cultural depth that animation couldn't convey.

Driving Irohazaka as a Tourist

International Driving Permit

Same requirements as anywhere in Japan: you need a Geneva Convention-type International Driving Permit plus your home country license and passport. Obtain the IDP before arriving in Japan.

Rental Car Tips

  • Automatic transmission is standard in Japanese rental fleets. If you want manual, book well ahead and be prepared for limited options.
  • Small cars work best. The First Irohazaka is narrow. A compact car (Mazda 2, Honda Fit, Toyota Yaris) is more practical than anything large. If you want something fun, look for a Mazda Roadster (MX-5) or Toyota GR86.
  • Navigation: Set your destination to Lake Chuzenji (中禅寺湖) or Kegon Falls (華厳の滝). The navigation will route you through the Second Irohazaka automatically.

Combining with Nikko Sightseeing

Nikko is a UNESCO World Heritage site with stunning shrines and temples. A practical day plan: visit Nikko's Toshogu Shrine in the morning, then drive up the Second Irohazaka to Lake Chuzenji for lunch, and descend the First Irohazaka in the afternoon. The whole Irohazaka experience takes about 30 to 45 minutes including a stop at Akechi-daira.

Traffic Tips and Timing

  • Weekday mornings are ideal. The road is quiet, and you can set your own pace through the hairpins.
  • Weekend mornings in October are the worst time for traffic. The autumn foliage draws massive crowds, and the road can back up severely. Tour buses compound the problem.
  • Arrive before 7 AM during peak foliage season if you want to actually drive rather than crawl.
  • Night driving is permitted and transforms the experience. The hairpins in darkness, with only your headlights and the stone markers passing one by one, is atmospheric. But the First Irohazaka at night is serious — the narrow road and tight turns require full concentration.
  • Winter: Check conditions before going. The road remains open but can be icy. Snow tires are mandatory and chains may be required during heavy snowfall.

Nearby Roads and Facilities

  • Lake Chuzenji — The lake at the top of Irohazaka is a scenic area with restaurants, boat rentals, and walking trails. Good for a mid-drive break.
  • Kegon Falls — One of Japan's most famous waterfalls, a 97-meter drop visible from a viewing platform near the top of the Second Irohazaka.
  • Konsei Pass — Continue west from Lake Chuzenji on Route 120 toward Konsei Pass for more mountain driving. The road is less famous but beautifully quiet.
  • Nikko town — Full range of facilities: fuel, food, accommodation, convenience stores.

Fuel: Fill up in Nikko before starting. There are no gas stations on Irohazaka or at Lake Chuzenji.

Hazards and Things to Watch

  • Tour buses on the uphill (Second Irohazaka): Large buses use this road to reach Lake Chuzenji. They're slow through the hairpins and impossible to pass safely. Patience required.
  • Monkeys: Wild macaques live in the Nikko mountains and occasionally sit on the road. They're generally not aggressive but don't try to feed them from your car.
  • Steep gradient: Both roads are steep. Use engine braking on the descent. Brake fade is a real risk if you ride the pedal through 28 hairpins.
  • Wet conditions: The forest canopy keeps the road surface damp longer after rain. Wet leaves in autumn are particularly treacherous on hairpin apexes.
  • Ice in winter: The road is at altitude and north-facing sections freeze early. Black ice is a genuine hazard from November through March.
  • Limited phone signal: Cell coverage is spotty in the mountains. Download any maps or routes to your phone before leaving Nikko. Rods works offline with GPS-only pace notes, which is exactly the kind of tool you want on a mountain road with no signal.

For more on the broader world of touge driving, including the culture, cars, and philosophy behind Japanese mountain pass driving, check out our complete guide.

FAQ: Irohazaka Pass Driving Guide

How many hairpins does Irohazaka have? Irohazaka has 48 hairpin turns in total — 20 on the uphill Second Irohazaka (Route 120) and 28 on the downhill First Irohazaka. Each hairpin is marked with a character from the classical Japanese iroha poem.

Is Irohazaka free to drive? Yes. Both the First and Second Irohazaka are free public roads. There are no tolls. You'll encounter tolls on the expressways getting to Nikko from Tokyo, but the mountain passes themselves cost nothing.

What is the best time to drive Irohazaka? Mid-October for autumn foliage — the mountain is covered in red, orange, and gold. For the best driving experience with minimal traffic, visit on a weekday morning. Arrive before 7 AM during peak foliage season to avoid tour bus congestion.

Is Irohazaka in Initial D? Yes. Irohazaka appears in the Initial D manga and anime. The most memorable scene features a Nissan Sil-Eighty on the downhill hairpins. The real road is narrower than the anime depicts, but the hairpin character is accurate.