In some areas of the country, dragon’s teeth road markings were introduced about two years ago, but as more vehicle movements take place over the summer, more and more people have seen them, and subsequently wondered what they are about and if there are any specific rules to follow.
Inappropriate speed is one of the main causes of road traffic incidents, and these markings, which consist of triangles painted along the road horizontally that resemble dragon’s teeth, hence the name, are all about controlling speed in vulnerable areas.
The horizontal traffic signals were put to the test “in an experimental phase”, as announced by the Ministry of Transport, Mobility and Urban Agenda in September 2021 in Nava de Roa (Burgos) and have been progressively implemented in other municipalities such as Caldas de Reis, Cuntis, and Castro Loureiro (Pontevedra).
How do they work? The dragon’s teeth create an optical illusion that makes the lane appear narrower than normal. In this way, when passing through a point marked with the teeth, drivers tend to naturally reduce speed and increase caution. According to experts, the human eye, when perceiving lines on the sides, interprets that the lane has narrowed, so it encourages the driver to lift the foot off the accelerator, thereby reducing speed.
These types of signs, which are 30 metres long, are usually located next to pedestrian crossings, sections with a high concentration of incidents or black spots on the roads.
Despite being operational for two years, the markings are still in the implementation phase.
