In Philadelphia, there is a significant investment in public transit including regional rail, an extensive bus system, a subway and trolley routes covering other parts of the city. There are even some well known bike paths in certain parts of town that make riding a bike comfortable and not as frightening as it might be in some large cities.
There are also of course the standard mix of surface streets and highways, some of them famous for terrible traffic like I-95 running north and south through the city and I-76 which runs east to west and is incredibly prone to backups as it travels along the Schuylkill River into the city.
As someone who lives very close to work and often walks or rides a bike, the largest annoyance is cars being driven at dangerous speeds and without consideration for pedestrians or cyclists. Generally the public transit system is convenient if not always timely and reliable but in our lives we rarely depend on it so it is easier to feel positively about it without that dependence.