I've run this marathon 3 times, each with a different experience based on what I was training for, the weather, and how it played out. But some things are consistent, such as the fast flat course and the incredible fan support.

My first race was in 2001. It was my first marathon ever and I was just hoping to finish. I ran slow and steady. I finished in 3:52 and didn't feel like I really challenged myself.

In my second Chicago marathon, I pushed pace more and finished in 3:29. This was probably my best experience.

In my third Chicago marathon, I followed a much harder training schedule with the goal of breaking 3:15. All my training analytics gave me confidence I could do it. In fact, my training predictor had me at 3:12. However, race day weather was very warm. I still tried to push myself and was on pace to break 3:15 at the 16 mile mark. But the heat took it's toll, and things started to fall apart in the last 10 miles. I finished in 3:36 and it was a pretty bad finishing experience.

Although I haven't done any other marathon, I can't imagine there being more fan support than you receive in Chicago. Fans line the streets and bridges for almost the entire 26.2. In fact, the fans are usually several people deep. In my second and third marathons, I wore my name on my shirt in big bold letters. The fans made me feel like a was a celebrity. My name was constantly being yelled out with cheers of support. It was very uplifting.

I highly recommend this marathon for anyone looking for a flat course with a lot of fan support. The only potential downside is the weather. The race is always in mid-October, which in Chicago means it is highly unpredictable. I'm sure you can look up the actual statistics, but my perception is that the weather is usually ok, but every few years there seems to be a real hot one.