Puerto de la Cruz is a generally safe city to visit in Spain. Petty crime like pickpocketing can occur, specifically in crowded areas and popular tourist sites, but it's infrequent. It's advised to keep valuables secured and remain aware of your surroundings, especially at night. The locals are friendly and protective towards visitors, including solo female travelers. It's always essential to exercise usual travel precautions, no matter how safe an area appears.