S-64a
Mandatory cycle lane alongside one-way roadway
Indicates, on one-way roadways, that cyclists must use the lane over which the sign is placed and that other road users may not use it. The arrows show the number of lanes on the roadway.
Category: Lane signs
Source: General Traffic Regulations (RD 1428/2003), Annex I; designs per the official sign catalog (RD 465/2025)