Roads are optional. Their function is only to add Happiness. They do not need to be used in a realistic way or to provide access to a particular tile.Many people do not use roads as they take up space and only add to Happiness (excluding the useless Village Road).
Unlike Pavement tiles, they may not have any Decorations placed onto them.
The Village Road, while free in unlimited quantity, offers no Happiness per tile.
Although "Royal" is usually the highest state of an item (eg:Royal Academy) there is a type of road called a Grand Road which is of a higher state than the Royal Road (The Royal is unlocked in level 20 and the Grand is unlocked in level 25).Even more suprising is that there is no Grand Pavement only a Royal one.Some people think that Grand is more inferior than Royal (according to the name) but they are wrong.