The Sundered Sand is the south-eastern quarter of the Kretavic desert, past the last wells of the Kharsa. Nobody lives there. It is drier than the interior and emptier than the map suggests, and even without its reputation it would be poor country to settle. It has a reputation regardless.
Crossing it
The Ember Road ends at Tal Marid, a well-town of perhaps three hundred people that exists to hire out guides, sell water and buy back whatever a party decides it does not need after all. Guides from Tal Marid will take a caravan across. They charge roughly three times the rate of an equivalent stage in the Kharsa, they refuse night marches, and they will not camp twice in the same place. Ask why and you will get a shrug, or a story.
Caravans that make the crossing do it because the alternative is six weeks around. Most do not. The standing advice in Halwan is that a cargo which cannot bear six extra weeks is a cargo you should not have taken.
What travelers say
The stories are old, and their consistency is the reason people repeat them. A rider comes into camp three days before he set out and cannot be talked out of the date. A camp burns down every night and stands whole every morning, ash and all gone by first light. A man walks out of the sand speaking of forty years away and has not aged a season, and knows names nobody has used in a lifetime.
Guides add smaller things that never reach the tellers in the coffee houses. Tracks that cross your own from ahead. A tally that comes out one short at noon and right again at dusk. The habit of counting the party twice a day, out loud, is universal down there and no guide will tell you it is superstition.
What scholars say
Kretavic scholars have argued about the Sundered Sand for centuries without settling anything. One school holds the place divine — a mark left deliberately, for instruction or for judgement. A second holds it diabolical and argues that the stories are temptations rather than events. A third, the least popular and the hardest to argue down, holds that it is simply a flaw: a scar in the country that never healed properly, no more meaningful than a crooked bone. The argument has produced a respectable library and no conclusions.
Feldian scholarship, most of it written by men who have never crossed the Sea of Coin, tends to file the whole business under caravan drink-talk. Kretavic writers find this funny in a way they are careful not to explain to visitors.
What is actually traded
Guides, and nothing else. The Sundered Sand produces no crop, no ore and no water worth the carrying. Its one reliable export is men who know the safe stages, and they are paid well, and most of them stop going out before they are forty.