S-603
Supplementary confirmation with exit advance sign
Indicates, on an autopista or autovía, the names of provincial capitals not adjacent to the autopista or autovía being traveled and their distances in kilometers. It also shows the identification boxes of the autovías or autopistas giving access to those towns. The upper sub-panels also show the corresponding exit number and the distance to that exit.
Category: Confirmation signs
Source: General Traffic Regulations (RD 1428/2003), Annex I; designs per the official sign catalog (RD 465/2025)