It's been some years since I've been in Chicago and I routinely used the subway. Just curious if that's still a good idea and for four days what if any pass should I get?
Chicago public transport is pretty safe and easy to use, you can buy 1, 3 or 7 Day Passes for $10, $20 or $28 for unlimited rides on all CTA buses and trains. There is a good app to use for CTA called Transit Stop. If you bring a car, parking can be very expensive.
The El is great! You can buy a Ventra card for any amount over $5 depending on how often you will take it.
On a recent trip to Chicago I took the subway from the airport to downtown and found it very easy and faster than trying to take a cab.
Kimberly gave you a link for Metra which is suburban trains, I think she meant to give you the CTA link which is for the el and buses inside the city.
You can find the info on passes here, you should be able to pick up at both airports but I'm not sure if you have to get a Ventra to get a multiday pass as the link below just addresses disposable 1 day passes. The ride from O'Hare is $5 by itself (the only upcharge in the system). For 4 days you might want to get a 7 day pass as the 3 day + 1 day is more than the 7 day. Travel to/from the airports are included on the passes
Hi John, public transportation is still good! I recommend getting a pass, you'll save some money. Check this site for passes! http://metrarail.com/metra/en/home.html