Erebor and The Misty Mountains

[Mithrandir]

I was wondering, if anyone here knows of any source (canonical, speculative or otherwise) which states what the physical heights of the Misty Mountains and Erebor are.

I'd be very grateful to anyone who can find me this information.

[Taurendil]

     I doubt there's any source which could provide the exact information on this (seeing as you haven't found it) but we may speculate from what we know about the mountains. It is told in the Hobbit that Erebor has ice on its top. So it must be no less than 1,000 meters above the level of the sea(supposing Middle-Earth is same Earth we are living on; the level of the Belegaer is roughly of the same level of our oceans and the climate of that land is similar to that of Northern Europe). Still, it's not a very big mountain, since goblins in the Battle of the Five Armies could swiftly reach the eastern and southern spurs of the mountain which were manned with wood elves and lake men and attack them from above. Personally I'd put it's hight between 1,500 and 2,500 meters, although the latter number is very rough.

     As for the Misty Mountains, there is the highest peak of Middle Earth. A speculation can be made from the fact that Endless Stair lead to the peak. It was made by the Dwarves, hence there should be enough air there to work at that hight(not to mention to fight the Balrog). I suppose that peak isn't much higher than the Everest which is 8,848 as far as I remember or at least of the same hight. It couldn't be much lower either, because it's said in TTT that there were clouds below the peak. Now, if the highest peak(aka Zirakzigil) is somewhat about Everest in hight we may compare the whole range of the Misty Mountains to Himalayas whose average hight is 5,000 meters according to Wikipedia.  I guess the Misty Mountains are about of the same hight with many higher peaks though. They are also snow capped as mentioned  again in the Hobbit.

[Athelas]

   Idon't believe the Misty Mountains were anywhere near the elevation of the Himalayas. The elevation of the Himalayas is just too high to allow reaching the peaks without supplemental oxygen (unless you're incredibly athletic and acclimatized), and there's no evidence that Gandalf, who as you point out, battled the Balrog up there, was like that.
  I think that The Mistys were comparable to the Alps - even though the Misty Range was North-South and the Alps are East-West, a person in reasonable shape could ascend them as long as the climb wasn't too technically difficult. So I'd say the tallest peaks in the Misty Mountains were in the 4000 - 5000 m range. At least, that's my story, and I'm sticking to it!

[Taurendil]

    Fair point. Though the dwarves aren't men, so perhaps they don't need supplemental oxygen. Yeah, perhaps I quite exaggerate. After all I suppose there are clouds lower than 4000 - 5000 m, so Gandalf could be at a lower hight.

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