I can't clearly understand the meaning of these phrases
This phrase is from J. R. R. Tolkien's "Hobbit". Chapter 1 "The unexpected party", dwarves' song.
The phrases I can't clearly understand:
"For ancient king and elvish lord THERE MANY A GLEAMING GOLDEN HOARD".
"In places deep, where dark things sleep, in hollow halls beneath the FELLS". (What does the word "fells" mean here?)
"The dwarves, they heard the tramp of doom. THEY FLED THEIR HALL TO DYING FALL BENEATH HIS FEET, beneath the moon". (maybe I don't clearly understand "beneath his feet" because of the sentence that stands before).
Thank you so much in advance!

Question

Answer

This is an old form of modern English (sounds like a contradiction, but it isn't.  Modern English is about 500 years old.)
Anyway, "There lay many a golden hoard" - "there was a great number of stores of gold"
"Fells" is an old form, referring to a barren range of mountains or hills.
"The fled their hall to fall dying beneath the feet of doom" - 'Doom' is personified and takes the form of a person or being.

Answer

I think that Frank explained those sentences very well.

Reading Tolkien can be quite a challenge for a second language learner! Is there any way that you can get a copy of the text translated into Russian? When I'm reading a book in a second language, I like being able to refer to a copy written in my own language when I get stuck.

Happy reading!