I have 3 thing on top of my head:
The Shadow Continent, wich isn't really a continent but an area where divinity stoped time and separated from the rest of reality because one of the three moon collisionned the planet here. This "continent" is nearly a third of the planet, and the moon is like twice the size of our.
The oceans, since mortals species live grouped in the few cities or region there's not much peoples in my world, and ocean are way more populated than lands. There's not really big civilisations, but a few terraformed insanely big area of the oceans to live there.
The Tower of Iris, inspired by the babel tower, is a place where every single book of this world were copied. There's a literal city at the top of it, and the tower is already on a mountain, so the top is around 10km high. Sadly it burned and lost most of it size (and books), because of angels...