My idea here was that this bridge is the border crossing between two (probably not super-friendly) countries, but it could also be used as a toll bridge or a fortress entrance. Of course, tell whatever story with it you like, but, personally, I think you should arrange a scenario where your players get to throw people over the side. Your barbarian will love you for it.
Also, the tower on the right really looks like something from Super Mario Bros. All I can think of when I look at the side view is, “Your princess is in another castle,” haha.
There’s an annotated version and DM notes and all the usual stuff on the patreon.