Routing is complex. There are a lot of disparate pieces that come together to give users the ability to navigate a site. There is the address bar ui element which displays a url string on screen. There is back/forward functionality accessible through buttons, keyboard shortcuts or other input methods. There are <a> links which navigate to new content in various ways. There is url input through the address bar.
I appreciate a look into this world, but routing on the web isn't supposed to be very complex. One of the big simplicity wins of the web network architecture was that it was stateless almost everywhere, with hypertext as the engine of application state[1].
Anybody can write some HTML with some anchor tags and tie it to some routes declared in a server-side routing file. The back button will work. History will work. Refresh will work. Copy-and-pasting the URL into an email will work. It's so easy that even I can do it.