Your car has broken down and you're stranded on the longest bridge in the world. (What a coincidence)
Also odd that both parts of the bridge have been broken off too. Hmm...
I've realized my Modern Earth project is going to take too long, so I'm currently building this as a distraction and to put something up on this website.

So anyways your car broke down...
Scavange for resources to fix your car. (Yes, it will actually move)
Zombies were the reason you couldn't cross over to the island.
I don't know where this in the world is.
All I know is that your on a bridge.
Maybe even just live on the bridge and build a city.
I just might even add in traders for your hard working. (Command Block Shop w/ Experience Currency)
We hope you make it to your destination safely!
Build, Destroy, Travel, Survive.