Puebla is generally quite a safe place. However, as with all Mexican cities there are certain places to have your wits about you, or where lone women might attract more attention than usual. The area between 5 Norte and 11 Norte and 18 Poniente upwards is reputedly a bit dodgy after dark, although it’s not somewhere tourists commonly go anyway. Also avoid wandering alone at night between 7 and 11 Sur and south of 7 Poniente.