The surface of Arrakis consisted almost exclusively of dry dune deserts, hence the planet's alternative name, Dune. Various weathered mountain ranges stretched across the planet, breaking up the deserts and sheltering the limited native lifeforms. Rock outcrops also littered the planet's surface.

The atmosphere consisted of nitrogen and oxygen in measures compatible enough to allow human beings to live on the planet without respiratory equipment. The production method of atmospheric oxygen sufficient to sustain limited biological life is through sandworm metabolism, which acts like an oxygen-producing factory.

Vast reserves of water were located deep within the mountains of the planet, as well as within countless sandtrout. Small amounts of water vapor existed in the atmosphere and were harvested via windtraps.

The northern pole of the planet sat on a large plate of bedrock and was ringed by mountain ranges. Thus it was protected from sandworm incursion, until the Fremen, led by Paul Atreides, used atomics to destroy the Shield Wall shortly before he proclaimed himself emperor.

This geography, combined with the milder climate, made human habitation at the pole more comfortable and explained the presence of the capital city Arrakeen.