Double curveFlanders
261. Double curve
A double curve is a road section containing two successive curves in opposite directions. The first curve may turn left and then right, or right and then left.
The same warning sign may also indicate a longer succession of curves. Drivers should reduce speed before the first curve, remain within their lane and be prepared for the following curves to differ in direction, sharpness and length.
Wikimedia.org • Jean Housen • CC BY-SA
Which Belgian signs warn of a double curve?
Traffic signs A1c and A1d warn of a double curve or a succession of more than two curves.
Warning for a double curve, first left then right.
English • Traffic sign A1c • Dangerous bend. Double bend or a series of more than two bends, the first to the left.
Français • Signal routier A1c • Virage dangereux. Double virage ou succession de plus de deux virages, le premier à gauche.
Nederlands • Verkeersbord A1c • Gevaarlijke bocht. Dubbele bocht of opeenvolging van meer dan twee bochten, de eerste naar links.
Sources
SVG source: Commons.wikimedia.org
Vascer • Public domain. Original SVG unmodified.
🔗 Wegcode.be • Artikel 66. Gevaarsborden (NL)
🔗 Codedelaroute.be • Article 66. Signaux de danger (FR)
Warning for a double curve, first right then left.
English • Traffic sign A1d • Dangerous bend. Double bend or a series of more than two bends, the first to the right.
Français • Signal routier A1d • Virage dangereux. Double virage ou succession de plus de deux virages, le premier à droite.
Nederlands • Verkeersbord A1d • Gevaarlijke bocht. Dubbele bocht of opeenvolging van meer dan twee bochten, de eerste naar rechts.
Sources
SVG source: Commons.wikimedia.org
Vascer • Public domain. Original SVG unmodified.
🔗 Wegcode.be • Artikel 66. Gevaarsborden (NL)
🔗 Codedelaroute.be • Article 66. Signaux de danger (FR)
Can a panel indicate the distance to the first curve?
Yes. A supplementary distance panel may indicate approximately how far ahead the dangerous section begins.
Does a Belgian double-curve warning sign impose a speed limit?
No. The applicable regional, zonal, posted and vehicle-specific speed limits remain in force.
Must you sometimes drive below the permitted speed?
Yes. Drivers must adapt their speed to the curves, visibility, weather, traffic, road surface and condition and load of the vehicle.
Must you be able to stop within the visible distance?
Yes. Drivers must remain able to stop before a foreseeable obstruction, including one hidden beyond either curve.

Traffic rules
Flanders