SlopeJapan

An introduction to the traffic rules and road signs of Japan. Learn about driving, road safety and much more in our illustrated book, with answers to frequently asked questions.

For informational purposes only. Always follow official regulations. Some content and images were created with AI assistance.


14. Slope

A slope is a section of road that rises or descends noticeably. A steep slope can affect vehicle speed, braking distance, traction, visibility and the ability of heavy or low-powered vehicles to maintain a steady speed.

Warning signs may indicate a steep ascent or dangerous descent and may show the gradient as a percentage. Drivers should adjust their speed early, select a suitable gear and remain prepared for slow vehicles, bends and changing road conditions.

Steep street in Okamoto. (Setagaya, Tokyo, Japan)
Wikimedia.org • Kestrel • CC BY-SA
What does a steep-slope warning mean in Japan?

Japanese warning signs identify steep ascent or descent hazards. Keep a speed suited to the road and read any separate restrictions before entering a narrow or winding slope.

🔗 laws.e-gov.go.jp • Japan Road Traffic Act — Articles 30, 42 and 70

🔗 laws.e-gov.go.jp • e-Gov — current enforced Road Traffic Act, revision metadata and full text

🔗 npa.go.jp • NPA — Traffic Lights and Road Signs, official English definitions

🔗 npa.go.jp • NPA — traffic instruction handbook, sign groups and road use; read with current Act

Warning for a steep ascent. Warning for a steep ascent.

English • Traffic sign 212の3 • Steep ascent: 10%. Select a speed and gear suitable for road conditions.

日本語 • 212の3 • 上り急勾配あり:10%。 この先に勾配10%の急な上り坂があります。道路状況に適した速度とギアを選んでください。

Sources

🔗 Commons.wikimedia.org
🔗 Laws.e-gov.go.jp • 道路標識、区画線及び道路標示に関する命令、別表第一・第二
🔗 Mlit.go.jp • 国土交通省、道路標識一覧

SVG source: Monaneko • Public domain • Original revision 2013-06-19. Wikimedia original unmodified.

Warning for a steep descent. Warning for a steep descent.

English • Traffic sign 212の4 • Steep descent: 10%. Use an appropriate gear to avoid excessive speed.

日本語 • 212の4 • 下り急勾配あり:10%。 この先に勾配10%の急な下り坂があります。速度が上がりすぎないよう、適切なギアを使ってください。

Sources

🔗 Commons.wikimedia.org
🔗 Laws.e-gov.go.jp • 道路標識、区画線及び道路標示に関する命令、別表第一・第二
🔗 Mlit.go.jp • 国土交通省、道路標識一覧

SVG source: Monaneko • Public domain • Original revision 2013-06-19. Wikimedia original unmodified.

How should I approach a steep descent in Japan?

Reduce speed before the descent and select a suitable gear to help control the vehicle. Keep enough following distance and avoid building up speed that requires continuous heavy braking. A warning gives no fixed safe descent speed: the gradient, surface, visibility, load and vehicle can require a speed well below the legal maximum.

🔗 laws.e-gov.go.jp • Japan Road Traffic Act — Articles 30, 42 and 70

🔗 laws.e-gov.go.jp • e-Gov — current enforced Road Traffic Act, revision metadata and full text

🔗 npa.go.jp • NPA — Traffic Lights and Road Signs, official English definitions

🔗 npa.go.jp • NPA — traffic instruction handbook, sign groups and road use; read with current Act

What should I check when meeting or overtaking on a slope in Japan?

Japan’s Road Traffic Act prohibits overtaking near a hilltop and on a steep downhill slope, subject to the Act’s provisions. Do not treat an apparently empty road beyond the crest as a safe place to pass.

🔗 laws.e-gov.go.jp • Japan Road Traffic Act — Articles 30, 42 and 70

🔗 laws.e-gov.go.jp • e-Gov — current enforced Road Traffic Act, revision metadata and full text

🔗 npa.go.jp • NPA — Traffic Lights and Road Signs, official English definitions

🔗 npa.go.jp • NPA — traffic instruction handbook, sign groups and road use; read with current Act

1 Japan 2 Motorway 3 Expressway 4 Zone 5 Speed limit 6 Minimum speed 7 Footpath 8 Bike path 9 Shared-use path 10 Tunnel 11 Toll road 12 One-way traffic 13 Quay 14 Slope 15 Bus lane 16 Bus stop 17 Stop sign 18 Give way 19 Roundabout 20 Road narrowing 21 Pedestrian crossing 22 Railway crossing 23 Mandatory direction 24 Turn prohibition 25 School area 26 Overtaking 27 Crossing animals 28 Slippery road 29 Rockfall 30 Curve 31 Wrong-way driving 32 Roadworks 33 Crosswind 34 Height limit 35 Width limit 36 Weight limit 37 Radar speed sign 38 Selective barriers 39 Intersection direction sign 40 Traffic lights 41 Traffic lights warning 42 Pedestrian lights 43 Road markings 44 Driving licence 45 Location marker 46 Traffic mirror 47 Emergency telephone 48 Cycling route 49 Parking 50 No parking 51 No stopping 52 Disabled parking 53 Traffic management 54 Reversing 55 U-turn 56 Uncontrolled crossroad 57 Road surface 58 Provisional licence 59 Emergency exit 60 City limit 61 Horn 62 Licence plate 63 Charging station 64 Dangers 65 Pedestrian 66 Cyclist 67 Moped 68 Motorcycle 69 Car 70 Truck 71 Bus 72 Police 73 Ambulance 74 Pothole 75 Path 76 Particulates 77 Air pollution 78 Rush hour 79 Road code 80 Two-way traffic 81 Street gutter 82 Cargo bike 83 Forestry vehicle 84 Construction vehicle 85 Semi-trailer truck 86 Trolleybus 87 Speed pedelec 88 Delivery vehicle 89 Idling 90 Tow truck 91 Four-wheel drive 92 No vehicles 93 Bicycle 94 Motorcycle equipment 95 Tram 96 Rail track 97 Caravan 98 Trailer 99 Tow hitch 100 Fire truck ...