Up to 50 thousand people are expected at some huge events in Pittsburgh this Sunday, and that could mean some big-time traffic tie-ups.

The Pittsburgh marathon kicks off at the convention center at 7:30. You’ll find runners all over town all morning. They’ll be clearing out just in time for the Pens game, as gates open at 12:30. Then at 1:45, the International Eucharistic Rosary March winds through downtown. Finally, Pitt’s graduation at the Petersen Events Center begins at 2:00.

Public safety director Mike Huss says taking a bus or the T might be a good bet. And don’t forget, parking garages may be closed or fuller than usual.