I was going to do a post on UCI rule 1.2.064 bls, but Inrng already covered most of what I was going to write following Kuurne-Brussels-Kuurne.
Here's the rule in case you don't want to click on that link:
1.2.064 bis It is strictly prohibited to use sidewalks/pavements, paths or cycle paths alongside the roadway that do not form part of the course. Non-respect of this requirement is sanctioned in accordance with Article 12.1.040.14 bis, without prejudice to any other sanctions that may apply.
Cycling's a weird sport.
Actually, when you think about it a bit, this rule is just weird on its own. You can't ride on sidewalks, pavements, paths, or cycle paths along side the roadway that do not form part of the course.
This, apparently, is in contrast with roadways which are not part of the course, which are fine.
I thought it was already well established that in a race, any race, you must complete the entire course, which generally implies remaining on the course unless you plan on returning to where you left it. So it's not clear this rule changes anything, in principle. In practice, though, there's the written rules and there's the actual rules. That was, after all, a major theme of The Secret Race.