Warning signs

Tunnel ahead

A tunnel is ahead; prepare for changing light and follow any instructions about headlights.

A tunnel entrance is ahead, where lighting and visibility may change. Adjust your speed as needed and follow any signs about headlights.

The United Kingdom 529.1 shows a tunnel entrance inside a red-bordered white triangle. Sweden A26 uses a red-bordered yellow triangle with a tunnel symbol. In Canada, Quebec’s I-265 is a green information sign indicating a tunnel.

How it looks in each country

Official sign in each country; the code is its number in the national rules. Signs that come in two directions show the left and the right version.

ArgentinaCode P-15
BulgariaCode А38
CanadaCode I-265
ChileCode PE-5
ChinaCode 警 24
ColombiaCode SP-37
CroatiaCode A24
CzechiaCode A 21
DenmarkCode A44
GreeceCode K-40
IndiaCode II-61
IrelandCode W-162
IsraelCode 138
Malaysia
MexicoCode SP-42
NorwayCode 122
PortugalCode A20
RomaniaCode A14
RussiaCode 1.31
Saudi Arabia
SerbiaCode I-24
South AfricaCode W319
SwedenCode A26
Switzerland
TaiwanCode 警41
Thailand
UkraineCode 1.9
United Arab EmiratesCode 436
United KingdomCode 529.1
VietnamCode W.240

Image credits

Sign images from Wikimedia Commons, used under their licences.

Argentina P-15: Original: Vialidad Nacional - Ministerio de Transporte - Presidencia de la Nación Vectorization: Civitas13, Public domain
Bulgaria А38: มองโกเลีย๔๔, CC BY-SA 4.0
Canada I-265: Transports Québec, Public domain
Chile PE-5: Gobierno de Chile, Public domain
China 警 24: Standardization Administration of the People's Republic of China, Public domain
Colombia SP-37: Gobierno de Colombia, Public domain
Croatia A24: มองโกเลีย๔๔, CC BY-SA 4.0
Czechia A 21: Government of the Czech Republic, Public domain
Denmark A44: Bewitchedroutine, Public domain
Greece K-40: Gigillo83, CC BY-SA 3.0
India II-61: Indian Roads Congress, Public domain
Ireland W-162: Government of Ireland – Department of Transport, Public domain
Israel 138: Government of Israel, Public domain
Malaysia: มองโกเลีย๔๔, Public domain
Mexico SP-42: Original: Secretaría de Infraestructura, Comunicaciones y Transportes / Secretaría de Desarrollo Agrario, Territorial y Urbano Vector: Too Classy for This World, Public domain
Norway 122: Peter J. Acklam converted the original EPS file to PDF with Ghostscript and the PDF file to SVG with Inkscape., Public domain
Portugal A20: Fry1989 eh?, CC BY-SA 3.0
Romania A14: Gigillo83, CC BY-SA 4.0
Russia 1.31: Юкатан, CC BY-SA 3.0
Saudi Arabia: มองโกเลีย๔๔, CC0
Serbia I-24: Gigillo83, CC BY-SA 4.0
South Africa W319: Southern African Development Community, Public domain
Sweden A26: Government of the Kingdom of Sweden, Public domain
Switzerland: Bundesamt für Strassen (ASTRA), Public domain
Taiwan 警41: 中華民國交通部, Public domain
Thailand: มองโกเลีย๔๔, CC BY-SA 4.0
Ukraine 1.9: Government of Ukraine, Public domain
United Arab Emirates 436: มองโกเลีย๔๔, Public domain
United Kingdom 529.1: UK Government, Public domain
Vietnam W.240: Government of Vietnam, Public domain