235 S. 33rd St., Franklin Field, 215/898-6145,
Penn Relays dates back more than 100 years, making it the oldest recognized relay meet in the world. Each year in late April, massive crowds come to the University of Pennsylvania’s  Franklin Field to watch the world’s top track athletes compete.
The highlight and most popular event is usually the USA vs. World races on Saturday. In addition to the action on the field, there is a carnival atmosphere around the entire campus with food, crafts, and entertainment.