What'st the best way to keep bears out of your camp site?

[RonBurgandy]

I'm going up into the Sierras where bears can be a problem. Other than keeping your camp site clean and your food locked up, what's a good way to keep bears away? I've heard of people spraying ammonia around their campsite. Not exactly environmentally sound, but does that work? Any other ideas?

 

[grand lake bum]

keep your campsites away from bears dumbass

 

[tabishsultan]

Just hide your food and don't bother them.If you leave your food out in the open then the bears will come after the food.