The legendary home of Thingol and Melian. Let's collect every bit of inspiration, every picture we can find, and come up with the best possible way to depict this fantastic place.
Those are my favourites too!I'll post larger versions of that Roger Garland one because I love his Menegroth.
He shows plants growing inside, underground, which was something I also suggested in I think the Sleep of Yavanna thread. Probably inspired by this painting. Melian can probably make whole trees grown underground, given enough space, if she wants. With or without light, though of course Menegroth is very well-lit.
The only part of this painting I don't like is the spiky orange flower light fixture. I approve of flower light fixtures, but not these things.