Complex sentence: Broad Street often serves as the main parade route for Philadelphia sports championship parades, the most recent being for the Philadelphia Phillies' 2008 World Series victory; close to 2 million people lined Broad Street to watch the parade.
Split into simpler sentences: Broad Street often serves as the main parade route for Philadelphia sports championship parades. The most recent being for the 2008 Philadelphia Phillies; close to 2 million people lined Broad Street to watch the parade.