By Peter Martell
BBC News, Nuba Mountains, Sudan
Central Sudan's isolated highlands saw heavy battles during the civil war
"Welcome to the liberated areas," the official said proudly, greeting those climbing out the small aeroplane that had just bounced down on the sandy airstrip in central Sudan.
If one still remained unsure as to who controls the green hills at the geographical heart of Africa's largest nation, the arrival form spells it out.
The crest of the ex-rebel Sudan People's Liberation Movement/Army (SPLM/A) heads the form.
"Welcome to the Nuba Mountains," the official added with a smile.
The scattered settlements of green farms and thatch huts were a key base for the SPLA guerrillas in their fight against the Arab-dominated and Muslim north - a two-decades long conflict fought over religion, resources and ethnicity.
Wary of the future
Some two million people died and four million fled their homes, before a peace deal was signed in 2005.
The SPLM won regional autonomy for the largely Christian and black African south, with a referendum on its potential full independence slated for January 2011.
But that leaves out the Nuba.
The former southern rebel enclave lies surrounded by the north - and that makes many wary of the future.
"We are not part of the referendum that the south will hold," said Kamal al-Nur, a former rebel colonel, and now commissioner of the SPLM-controlled Heiban county.
"Instead, the Nuba Mountains will hold popular consultations to decide our future."
The 'next Darfur'?
However, analysts warn the "popular consultations" - which will also be held in the similarly contested Blue Nile state - are poorly defined and offer little realistic chance of settlement for the regions.
They include no set steps for either autonomy or to join the south - something many ordinary people assume will take place.
The SPLA flag shows who is in charge of the Nuba Mountains
The volatile region is already awash with automatic weapons, and fears are growing the region requires little to tip back into conflict.
"If the south does achieve independence, it will leave these two states in a very difficult position indeed, and it could easily trigger fresh violence," warned John Ashworth, writing in a September report for the advocacy group Pax Christi.
It is a concern shared by many of the Nuba peoples - some 50 mainly black African ethnic groups - who share much in common with those in the south.
"We worry about the future, because we feel we could stand alone," said former rebel soldier Abdulaziz Kuwa, who grows groundnuts and sorghum on small hillside farm.
"I support the SPLM, but I fear the north will not let our farmland go without a fight."
The mountains, stretching for some 48,000 square kilometres (19,000 square miles), rise out of the wider South Kordofan state - a region with rich oil reserves.
Few believe the government in Khartoum would easily surrender such wealth to their former civil war enemies in the south.
A report last year from the International Crisis Group dubbed South Kordofan the "next Darfur", because of the potential for violence between the rival different Arab and African groups.
Memories of the war remain bitter, with old enmities exacerbated by pressure on grazing land.
People are free to drink traditional sorghum beer - unlike in Khartoum
Nevertheless, many people here appear loyal to the rebellion's original aim: equality within a united Sudan.
"We have three religions in the Nuba - Islam, Christianity and traditional beliefs - and we all live together without problem," said Jabir Hamid, drinking home-made sorghum beer in the market.
"The north would make us have [Islamic] Sharia law, and we would not allow that - that is what we fought to end."
The Nuba even take Wednesday as their weekend: a day chosen so as not to favour the holy day of any religion.
But the south appears determined on secession: southern president Salva Kiir said in October that voting for unity would make southerners "second class" citizens.
With Sudan's first presidential, legislative and parliamentary elections for 24 years due in April, tensions are running high between north and south.
Life is deceptively calm in parts of the Nuba Mountains
Cynics predict electoral failure, but the Nuba say the ballot could be one of the last chances to decide their future in peace.
"If we can't elect the people who represent our views in these elections, then our voice will not be heard in the popular consultations," said Younan Bashir Kuku, an SPLM member at a training course in preparation for the elections.
It is a critical time for all Sudan.
"The Nuba people fear the breakaway of the south because they will be left as an isolated minority in the north - and will also be on the frontline of any future north-south conflict," said Peter Moszynski, a Sudan analyst who began working in the Nuba in 1981.
"Unless they are offered some form of special status in northern Sudan many could return to the armed struggle, as they insist that they will fight for their right to be Nuba, and not be further assimilated into an Arab Sudanese state," he added.
Reports that civil war era militias are regrouping are confirmed by the commissioner.
"The militias have many guns and they are becoming active, " said Mr al-Nur.
"Security is our main concern, especially with the elections coming."
The future of the region may not be clear but one thing seems certain - for the Nuba Mountains, there are tough times ahead.