I have a tip.
First step is to collect 10 reference pictures of what you want to draw and make a reference/mood board.
Next step is to think about what big elements you want in the Olympus that you want to draw.
Stairs, one main building, 5 smaller one, 3 kind of gates (I don´t know what it´s all called, just
making things up), hills in the background etc.
Then draw a rough plan (like an architect blueprint thingy) and then draw a rough sketch without thinking about perspective,
just throw the elements on the canvas
Then you can think about things like ground level, horizon line, perspective and grids and work on the rough sketch that
you made in step 3.
The biggest mistake (imo) that you can do is to draw with perspective grids before you know where the journey is going.
It will end up in a stiff drawing and I don´t think the result will be good. There is a principle called "work from big to small"
and this is very important for drawing backgrounds.
I learned step 3 from an experienced german comic artist some years ago who gave me feedback on my super stiff backgrounds.
It is so much easier when you first throw everything on the canvas and then start working on it.
Bonus tip that I often do after step 3 when I work on buildings. I construct everything in a 3d architecture app and make
my own 3d models of the buildings. I would do a super rough one for olympus. It´s sometimes easier to work like that instead
of drawing everything from scratch with guidelines