Spec. Steven Manley has begun to notice changes in this ravaged country. When he arrived last August, he saw a great many blown-up buildings. But now, here and there across Bosnia, people are starting to rebuild.

Parts of Bosnia remain a country of ghost towns, monuments to a war of genocide based on ethnic background. During the three years that the conflict raged, whole populations were murdered or displaced. All that remains of some regions are deserted villages where every house and store are rubble.Still, people are feeling a little more sure of themselves. At least near the bases of coalition forces that intervened to end the fighting, people are mixing cement and building new homes of cinder block, brick, reddish-orange roof tile - sometimes using material scavenged from destroyed houses.

Manley, a 21-year-old from Layton, Utah, doesn't think that means the conflict is over. Not by a long shot.

"Just recently, they were supposed to have a resettlements of Muslims into a Serbian town," he said. As in many areas of Bosnia, Serbs had chased out Muslims in the name of "ethnic cleansing" and taken over their houses.

Under the Dayton agreement that ended the war in 1995, refugees are supposed to be allowed to return to their homes. But in this case, Manley said, as busloads of Muslims returned to their hometown, a Serb mob of 500 "attacked the buses. They destroyed three cars and flipped a bus over . . .

"We had to go in there, take them out, so they weren't injured."

From Mount Vis itself, a commanding 459-foot hilltop 10 miles southeast of Tuzla, Manley pointed out Muslim villages that had been shelled by Serbs troops who once held this position. The towns were clustered among sea-green fields and on the slopes of steep little mountains. The air was hazy with smoke, as farmers burned some of their fields for spring planting.

He pointed toward Kalesija, the nearest village, showing white buildings with orange-red rooftops and a slender, minaret spire. "Up here the Serbian army used to pelt it constantly with fire, all the time, mortar fire, air-gun fire," he said.

"They used to fire all their weapons down on the Muslim cities surrounding the hill."

The Serbian commander of Mount Vis had a warning for the commander of the American troops who took over the post in January 1996. The Serb reportedly said he would be back in a year's time to assume control of his hill.

"I don't know if he expected us to pull out or if he expected to actually take it over, but he hasn't come back."

The position has been rebuilt as an American outpost. American engineers collapsed the Serb trenches and bunkers, shoving logs and dirt into them.

But the lines are easily visible with their breastworks of logs and sandbags. A box of rusting 50-caliber machine gun shells shows where a gun emplacement once was. A broken ammo chest, stenciled with Cyrillic characters, lies near a destroyed bunker, a log hut with dirt over it.

Today, Mount Vis is a lonely base where a small contingent of American soldiers man radar, communications gear and lookout towers. Its garrison rotates in and out of the larger base, Camp Dobol, about five miles to the east. When they're not here, they work at Camp Dobol, checking vehicles, or are on patrol in heavily armed Humvees.

At all times when they patrol the countryside, the troops must remain alert for land mines. Recent estimates of their number range from 750,000 to 3 million.

Manley and a few other soldiers were on duty at a checkpoint beside a road just outside Camp Dobol when they heard an explosion. "So we sent out our QRF - which is Quick Reaction Force (a special team that reacts to dangerous situations) - to see what the explosion was," he said.

"And they went out there, and they said a guy was walking through his field and he stepped on a land mine."

That man was killed while a companion was badly injured.

"They put his friend in a van and were driving him to the hospital, and they came right to our checkpoint," Manley said.

Wrapped in a blanket, the injured man was shaking and covered with blood. He was "white like he'd lost a lot of blood."

Soldiers loaded the dead man on a trailer and took him away, Manley added.

Nothing quite as shocking happens on Mount Vis, however.

Soldiers keep a close watch on the dirt road from their wooden watchtowers. An M-60 machine gun and a dark-green ammunition box are propped beside the clear plastic window, a log book and pens on the unpainted wooden table.

"We have to check IDs of everyone coming in and out, make sure they have their SFOR (for "Stabilization Force") clearance and search the vehicles, you know, make sure that they're not trying to sneak anything in an out."

The most exciting event recently on Mount Vis happened in April, he said.

"The farmers were burning their fields and it got out of control, and fire came up to the top of the mountain and we had to go fight the fire before it came to our base camp," he said.

Soldiers hooked up a hose to a water truck and sprayed water onto the blaze, controlling it at the fence line.

But even ordinary field fires can sound uniquely Bosnian. "You can hear land mines going off from the fire setting off unstable mines," he said.

Sunday: On patrol in a danger zone