Back to the environs...
I would like Melkor's entrance to Arda to break the ground he walks on. So it is immediately visually clear that his presence there is making this into Arda Marred.
My first thought for this is the Giants' Causeway in Northern Ireland:
At the very least, a volcanic rock formation would serve us well (no Sea, of course - ignore that).
Kilauea in Hawaii is another natural option:
It doesn't have to look completely ruined and desolate yet, but the immediate impression should be that this place is far from habitation - remote, stark.
I would like Melkor's entrance to Arda to break the ground he walks on. So it is immediately visually clear that his presence there is making this into Arda Marred.
My first thought for this is the Giants' Causeway in Northern Ireland:
At the very least, a volcanic rock formation would serve us well (no Sea, of course - ignore that).
Kilauea in Hawaii is another natural option:
It doesn't have to look completely ruined and desolate yet, but the immediate impression should be that this place is far from habitation - remote, stark.

