Government forces in the Democratic Republic of Congo have pushed rebels back 5km (three miles) at the front line north of the eastern city of Goma.
The BBC's Mark Doyle says the two sides are now separated by a dormant lava field created by a nearby volcano.
In Goma, hundreds of women have protested to demand protection from rape and peace in the region.
The UN says it is to move 60,000 people from a camp north of Goma to a location west of the city in case of fighting.
The people at Kibati camp, close to the front line separating government troops and rebels loyal to Gen Laurent Nkunda, are among 250,000 who have fled the violence which flared in August.
The UN refugee agency said aid workers have plotted out the new site - called Mugunga III - and most people will have to make the 15km journey there by foot.
Fighting has stopped aid from reaching Kibati and forced many there to flee south to the provincial capital, Goma.
Our correspondent says the front line is now just beyond two strategic hills, on top of which government forces have placed spotters and artillery.
The distance between the nearest opposing troops is just a few hundred metres, he says.
On the rebel side of the line he saw rebel soldiers consolidating their own, high, ground - more hills from which they could target the government forces on the road below.
The United Nations peacekeeping force in DR Congo wants the two sides to move further apart to minimise the possibility of accidental clashes which could exacerbate the already disastrous humanitarian situation.
In other developments:
FORCES AROUND GOMA
CNDP: Gen Nkunda's Tutsi rebels - 6,000 fighters
FDLR: Rwandan Hutus - 6,000-7,000
Mai Mai: pro-government militia - 3,500
Monuc: UN peacekeepers - 6,000 in North Kivu, including about 1,000 in Goma (17,000 nationwide)
DRC army - 90,000 (nationwide)
Source: UN, military experts
- The EU is to discuss sending aid and how to bolster the UN force
- The US and UK have urged the UN Security Council to approve a request from the UN for 3,000 extra troops
- UN envoy, former Nigerian President Olusegun Obasanjo, is to hold talks in the capital, Kinshasa, before going to Goma at the weekend
- He will be joined by former Tanzanian President Benjamin Mkapa and an unnamed Southern African leader in a bid to prevent the conflict escalating
- DR Congo's Foreign Minister Alexis Mwamba Thambwe is in the Rwandan capital, Kigali, for talks, AFP news agency reports.
There have been reports - all denied - that troops from Rwanda, Angola and Zimbabwe are in DR Congo, fighting on opposing sides, as they did in the conflict which officially ended in 2003.
UN troops have reinforced their positions in Goma and say they will prevent the rebels from taking the city, as they have threatened.
On Thursday, Gen Nkunda's rebels - who are demanding protection from Rwandan Hutu rebels who fled to DR Congo after Rwanda's 1994 genocide - told AFP they had advanced to the outskirts of the strategic town of Kanyabayonga, 100km (60 miles) north of Goma.
Government forces were accused of looting and raping civilians there earlier in the week.
The UN has accused both sides of war crimes during the latest upsurge in violence.
On Friday, women, some dressed with black bin liners covering their hair, gathered at a sports stadium in Goma housing thousands of people who have fled the fighting.
They held up signs saying: "We mourn our children killed in Rutshuru" and "Enough of camp life".
"Women are tired of this war. We are just the victims. All people involved in this war are raping," one demonstrator, Solange Nyamulisa, told the BBC's Focus on Africa programme.
A spokesman for the charity ActionAid told the BBC cases of rape and violence against women have risen dramatically since the latest fighting broke out.