If you've ever wondered what it's like to watch one of these races live at the scene instead of on TV.... it's basically lots of waiting around inbetween a load of support vehicles rumbling through, accompanied by sporadic bursts of many people famous for riding bicycles passing through so fast you can't really figure out who's who.

To give you an idea, I headed outside around 1:54pm and over by around 3:20pm - this video squishes it down to around 19minutes of what there was to see when things were happening during this time.
http://www.youtube.com/watch?v=dZbzVxbQaSQ