[senocular]

I think it will contain at least the island to the east that the unfinished bridge leads to (the airport?). You can see it on old maps.

• Burnout 5 - Route Map?*|*The Average Gamer

And in the game, you can get a pretty good look of the island looking out over the water from this bridge

• Burnout Paradise™ Paradise City Interactive Map - A custom location within Paradise City with dynamic content

As well as a number of different places there along Angus Warf.

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What I'd really like to have is a destruction derby arena/mode. I loved those games for the PS1 and Burnout is I think the closest I have to something like that now.