TunnelPortugal
1. Tunnel
A tunnel is a covered passage that carries a road through or beneath an obstacle such as a hill, mountain, building, waterway or another transport route. Road tunnels may contain one or more traffic lanes and can carry traffic in one or both directions.
Driving in a tunnel requires particular attention because visibility, available escape routes and space for avoiding hazards are limited. Drivers should follow the applicable lighting, speed, lane and following-distance rules and pay attention to emergency exits, traffic signals and variable-message signs.
What should I check before entering a tunnel in Portugal?
In a tunnel signed as such, use dipped headlights even during the day. The Road Code separately prohibits U-turns, reversing and ordinary stopping or parking in tunnels.
🔗 ansr.pt • ANSR official RST — corrected 2019 republication, sign descriptions and markings
Does a tunnel sign in Portugal set a universal speed limit?
No single speed can be read from the tunnel pictogram. Apply the road’s relevant limit and any permanent or electronic speed restriction, and drive more slowly when visibility, queues or another hazard require it.
🔗 ansr.pt • ANSR official RST — corrected 2019 republication, sign descriptions and markings
Start of a tunnel.
English • Traffic sign H35 • Tunnel. Indicates a tunnel; its name may appear at the bottom of the sign, and its length is given on a model no. 2 supplementary plate.
Português • H35 • Túnel. Indicação da existência de um túnel, podendo o nome do túnel ser indicado na parte inferior do sinal cuja extensão é dada por painel adicional do modelo n.º 2.
Sources
🔗 Commons.wikimedia.org (Gigillo83 • CC BY-SA 4.0)
🔗 Diariodarepublica.pt • Regulamento de Sinalização do Trânsito • artigo 34.º • H35
🔗 Ansr.pt • Republicação oficial retificada • H35 • página 21
Image via Commons.wikimedia.org
Gigillo83 • CC BY-SA 4.0 • Source revision 2015-03-09. Wikimedia original unmodified.
Warning for a tunnel.
English • Traffic sign A20 • Tunnel. Warns of a tunnel ahead.
Português • A20 • Túnel. Indicação da proximidade de um túnel.
Sources
🔗 Commons.wikimedia.org (Fry1989 eh? • CC BY-SA 3.0)
🔗 Diariodarepublica.pt • Regulamento de Sinalização do Trânsito • artigo 19.º • A20
🔗 Ansr.pt • Republicação oficial retificada • A20 • página 10
SVG source: Fry1989 eh? • CC BY-SA 3.0 • Original revision 2015-03-16. Wikimedia original unmodified.
Is every tunnel in Portugal open to pedestrians and cyclists?
No. Check the road category and access signs before entering. A motorway tunnel, a vehicle-restricted tunnel and a purpose-built walking or cycling underpass have different access arrangements. Emergency evacuation routes do not establish ordinary public access.
🔗 ansr.pt • ANSR official RST — corrected 2019 republication, sign descriptions and markings

Traffic rules
Portugal