Reference to this StackExchange question
In the classic Microsites, we were able to add a "folder"-like structure to the personalized URL, i.e. https://pages.s7.exacttarget.com/foldername/something/
But in CloudPages, if you try to do the same thing it doesn't work. After publishing the page , the page shows a "Bad Request." But removing the "folders" in the personalized URL for the same page corrects it.
It makes for easier to organize paths in the URL rather than having everything in the root domain.