What does this sign mean?
En español: ¿Qué significa esta señal?
Why this is the correct answer
Indicates the kilometre point on a road, which is not a motorway or dual carriageway, when this point is a multiple of 10. The colour corresponds to the network to which the road belongs: ORANGE: First-level regional road (see sign S-430). GREEN: Second-level regional road (see sign S-440). YELLOW: Third-level regional road (see sign S-450).