Is there permanent dry ice on Mars? Are there any places featuring permanent dry ice (carbon dioxide ice) on Mars?
Is there dry ice at the poles?
Yes.
The Southern polar ice cap has a covering of $\mathrm{CO_2}$ about 8 m thick that doesn't completely disappear in summer. It remains in &quot;pits&quot; of up to about 1km in diameter.  The  thinner dry ice layer in the North sublimes completely into the atmosphere in summer. [source]