Take the CTA Blue Line to the Clinton L stop. From there, walk one block south on Clinton, then west on Harrison till you get to the Greyhound bus station (11/2 blocks). Which is located between Desplaines St. and Jefferson St., on Harrison. This is for the main Greyhound bus terminal, btw. Certain Greyhound buses(you'll need to look up bus schedules on your own) will stop at the Cumberland Blue Line station, and also 95th/Dan Ryan Red Line station. These 2 locations are bus stops ONLY where you'd need to buy tickets in advance, and can't buy bus tickets right at those locations.
Sorry i don't know about bus
Taxi.
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