More than 100,000 people have sought refuge here, fleeing interethnic violence and famine.
But even in the camp, there is no guarantee of safety. Annan listened as refugees complained about alleged attacks by police and Arab militias.
And Darfur is not the only humanitarian crisis facing Sudan.
Annan on Friday appealed for more international aid for Darfur as well as for southern Sudan, where a January peace deal between rebels and the government ended more than two decades of civil war.
"We do have problems in the south; we don't have all the funding we need and it is just a shame that in the south we have a peace agreement but we don't have resources required," Annan said. "In Darfur, we don't have the peace agreement. But we have more resources in Darfur, and it looks as if governments have shifted the support they used to give to the south to Darfur. What we need is additional resources to cover both crises and we are appealing to donors to really help us to get the resources to get the job done."
In April, donors promised $4.5 billion to help the south recover from the civil war.
But warehouses at the Kenyan border used as a staging post for international food aid are almost empty.
Famine has forced many women to boil leaves and grass to prevent their children from starving to death.
And aid workers fear growing hunger will inflame localized conflicts and complicate attempts to implement the peace deal.
Patrick Murphy, of the aid agency Doctors Without Borders, said, "The world is going to be facing another problem area that it does not need. Governments and private individuals have worked very hard in the last 22 years to establish some kind of peace accord to happen. Now is a good opportunity to continue to support that, and one of the ways to support that is to make sure that people here don't starve to death, and starving people have a tendency to get upset."