1. Over 2,000 participants in the 5K and 10K combined started their Halloween festivities early with the Trick or Treat Trot at Chicago's Montrose Harbor.

2. Chicagoan Luis Samayoa, 24, was the class of the field in the 5K, winning in 15:28.

3. Andrea Depol, 28, topped the women's 5K field with an impressive time of 17:47 on a cool, breezy morning.

4. Several members of the Bohermeen A.C. were in Chicago from Ireland to support their friend Richie Byrne, a DePaul University sophomore, who competed in the Conference USA Cross Country Championships the previous day.

5. Once the race was over, the trick-or-treating began.

6. In a sprint to the finish, the yellow runner had a slight lead but the runner in red was able to "ketch-up" and they finished side-by-side.

7. The Girls on the Run (a non-profit prevention program that encourages preteen girls to develop self-respect and healthy lifestyles through running) showed up in full force with 554 runners for the 5K race.