Observation: I'm sitting in my office in Orland Park, Illinois using my relatively new Macbook Pro. I followed the link and, as soon as I arrived at the page, I saw a dialog to choose my location. About a second later these choices vanished, the page assumed that I was Indianapolis, and I was shown a list of events in Indianapolis.

Since I got no popup asking for permission to share my location, I assume that you are using my IP address to geolocate me, and while that is definitely not a very accurate way to geolocate, its accurate enough to place me at least within one town of my actual location.

Verdict: You should work on your geolocation method immediately, or you should disable the feature for end-users until you have time to focus on it fully.