YAY ANAstaseon!
We didn’t have any time to geocache in Chicago, but we did track our trip progress on our friends garmin rhino gps ( which after years of service, was on the fritz with the display blinking on and off.)
I hate to rain on the parade, but I will.
Homeland Security and the police have been alerted to “suspicious” behavior centered around hiding Geocaches.
Be careful out there- if they don’t understand it, it’s automatically dangerous.
Not necessarily.
Geocaching.com has a PDF brochure that you can print out. I keep several copies in my backpack.
The one time that SWMBO and I got checked out by the cops was really funny. We were looking for a cache down in Galveston, on Pelican Island. It was the last one of the day for us and the sun had just gone down. We were using flashlights, closing in on it, when suddenly the world lit up. A Galveston PD officer driving an SUV unit with a bigass light rack on it had turned on his floodlights. Our response was basically: "WTF?? :eek: Oh, it’s the cops. 
OH, LOOK, THERE’S THE CACHE!! 
" I’m not sure we would have found it without his floodlights.
When the officer came down, we explained what we were doing. Showed him the GPSr, showed him the cache, thanked him for his help with the floodlights and gave him one of the brochures. He got a laugh out of it and we probably got a convert to geocaching. He never even asked us for ID.