In Lightroom CC 2015, you’ve got a new Dehaze slider to work with. This is quite useful on landscape images in particular, to remove atmospheric haze, fog or even flare. It’s available exclusively in Creative Cloud, and not in Lightroom 6, though there’s a workaround that I mention here.
The Dehaze slider is located at the bottom of the Effects panel in the Develop module and you will be amazed at how easily it can clean up haze. Just be careful not to go overboard and move the slider too far to the right, or you could end up with vignetting (darkness at the corners) or noise, or colors that get too intense.
Also, it’s a good idea to set your white balance before dehazing because Lightroom takes the white balance into its calculations when using the Dehaze slider. Watch my tutorial to see it in action.