This past Sunday was the Tokyo Marathon and the course went right by my apartment so I went out to watch. It was in amazing amount of people going by. I heard that there were 30,000 runners. The race started at 10 in the morning and at 3 in the afternoon there was still a pretty steady stream of people going by my apartment, which was about 3/4 of the through the race course.
Probably the most entertaining part was that there were quite a few people running the marathon in costumes.