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First of all you want to take your black level to an acceptable black. Haze has the tendency to wash out the image, so the first thing is to balance the blacks.
Once this is done, you need to adjust the contrast/midtones, so that you can recover the gradients details in the areas between the white and black zones.
Usually you have to fine tune the blacks again after this step.
After that, you have to correct the color cast, which is usually on the blue channel. You want to take down the blues untill they don't represent a cast anymore, this depends a lot on your image, and there are cases when is a bit hard, especially if you were shooting very far snowy mountains.
All these things just require a single curve adjustment.
Levels are the same thing but you can't really adjust on a per-channel base and other than in a linear way.
Curves give you much more control.
A UV Haze filter helps a bit with that.