Huge City

I create a huge City as a model but the game turns slow.
Is there any way to speed up the game?.
Could i break the level up into parts and only load the area around the player?

Whats the best way for me to deal with this?.

Is it all one big model? Or a bunch of high poly models? Is it 999,999,999 quants across? If its all the same model it negates the LOD and that could be a problem. Please describe what it is, it could be a lot of things.

Basicly it started as terrain i then built on top of it so its one big model.
A few thousand polys, i can redisign becuase im not that happy with what i built.

If you are using Max I recommend a plugin called Greeble, you could make a city in seconds. But you would need to break it apart for the LOD

Thanks ill look that up.
So how do i use LOD to link up the little city parts?.
The Manual is not helping much? is there a tutorials ?
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Edit the Plugin is amazing, this link could anyone as well
http://digitalurban.blogspot.com/2008/03/greeble-3d-city-tutorial-2-cityscape.html
Its a great plugin 9/10.

Do you have pro edition? And if not,do you use lite-c/c-scripts ?

yeah i use script's, i got a7 extra.