1) Pretty flat course
2) Not many sharp curves
3) Plenty of pacers (Kipchoge did have obviously one more than officially allowed by just having one guy out of his team running in his group)
4) Bottle service (The elite have a dedicated person who drives with the bike and stops at each refreshment point and hands the bottles directly to the athlete)
5) Weather conditions are really good usually though it was almost a bit too warm
6) Atmosphere. There were never so many spectators at the streets. People love the marathon here and embrace it. Plenty of bands playing.
7) The last km through the Brandenburg Gate. It makes you give all because it's an historical moment.
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