Did they have portable toilets positioned at points during the race and did you have to use them? This is my biggest issue with any walking or running events on a road, beach or course. I remember back in the 1980s when I was at a Catholic high school and then suffering from very bad UC, we were compelled to do a walkathon for charity. I was frightened because the walk went through random residential neighborhoods and there was no place to go unless I ran into the woods. Somehow I made it although my guts were unsettled during the walk.
Some years ago my paralegal ran in (and completed) the NYC marathon. She told me that during the race she had to pee, so she found some bushes in Central Park which she thought gave her some privacy. Instead some guy had followed her and was watching! She was really upset about it. Anyway it's the bathroom issues I always think about with races and walks.