S-1
Autopista
Indicates the start of an autopista (controlled-access highway) and therefore the point from which special autopista traffic rules apply. The symbol may announce the proximity of an autopista or indicate an intersection branch leading to an autopista.
Category: General information signs
Source: General Traffic Regulations (RD 1428/2003), Annex I; designs per the official sign catalog (RD 465/2025)