Towers.

I have always seen Mountains as a more recurrent symbol, but these Mountains have had some very artificial aspects.

The most memorable 'Mountain' was very steep, and it was tiered, like a staircase, but all around.

yes, when I think of it for a moment, it would seem more like a Tower than a natural mountain. However, there had been vegetation upon it.

There was a Goddess of the Mountain and she told me from half way up the Mountain, "Only those at the bottom cannot go to the Top".