^^ Tire marks on the curb.
Car tires have very thin sidewalls nowadays to improve mileage. Rubbing a sidewall on the curb is a good way to get an unrepairable flat.
Not sure it if is your place [MENTION=429288]Kabuki12[/MENTION] but if so, whomever is parking their car with the tire against the curb might want to give a few inches more space.
-Tim-