Thirty years after a volcanic eruption wiped out the city of Armero, Colombia is still haunted by the tragedy, and by the wide black eyes of its most iconic victim.

The image seared into collective memory from the 1985 eruption and the deadly mudslide it triggered is that of Omayra Sanchez, a 13-year-old girl trapped in the debris who died after three days of futile efforts to save her.

Footage of Omayra pinned down in a pool of muddy water was broadcast around the world, raising an outcry over the authorities' failures in responding to a disaster that killed more than 25,000 people.

The young girl, who was conscious nearly to the end, bore her fate with quiet dignity as emergency workers struggled to free her legs from the mangled remains of her house.

They eventually gave up, deciding the best they could do was comfort her.

Three decades on, Omayra is still remembered for her pitch-black eyes, which stare out damningly in a picture that won the World Press Photo of the Year award.

What is left of Armero, however, is sinking into oblivion.

"Thirty years later, I still have nightmares," says Olga Villalobos, who was going on 13 at the time.

Like Omayra, she was trapped for hours by the avalanche of mud unleashed when the Nevado del Ruiz volcano erupted, melting its snowcap and causing a landslide.

She remembers how volcanic ash and rock rained down on the city the evening of November 13, 1985.

Her family tried to flee in their car, but got smashed by the wall of mud that came barreling down the Lagunilla river canyon at 300 kilometers (185 miles) per hour.

"There was a loud noise like a thunderclap. Then the water and mud washed into the car," Villalobos told AFP.

Suffocating, she feared she was dead.

"I let go of my mom and my little brother. That saved me," she said. Her loved ones both perished.

Today Villalobos is 42 years old, works as a translator and has two children. The only sign of her ordeal is a tiny scar near her eye. But she says she still hears the rooster crows that sounded just before the disaster.

- 'Sleeping lion' -

Locals called Nevado del Ruiz the "sleeping lion," but the volcano had been awakening for several months.

"There were tremors, ashes covering everything. The water was contaminated. But city hall just told us to cover our noses," said Alma Landinez, 56.

Every year, Landinez, who lost 14 relatives, returns to clean up the plot where she thinks the family house stood.

Not a scrap of it survived the mud, which has since given birth to a thriving burst of tropical vegetation.

"We didn't have the emergency response capacity we have today. This tragedy served as an example, and not just for Colombia," said Harold Trujillo, 50, a doctor who then worked for the Red Cross and lost 70 of his 90 coworkers.

- Ghost town -

Today, the few remnants of Armero are overgrown with trees. The top floor of the hospital, a hardware store and a phantom restaurant line the road into what was once a thriving hub of the cotton and rice industries.

Gravestones and decaying crosses scattered among the volcanic rock mark the spots where survivors think their loved ones lie.

Some of those who escaped were resettled in neighboring towns. Others never received anything. The government funds set aside for victims ran out after two years.

Except for some emaciated cows, the only signs of life are at Omayra's grave.

It is covered with flowers, plaques, angels and other religious offerings left by pilgrims who invoke her name almost as a saint's.

"We leave her notes to thank her or ask her favors," said July Amezquita, 29, as her husband carefully folded a message to leave among the candles and toys.

The former town square is the only spot that has been dug out from the mud. All that remains of the cathedral that once abutted it is a gutted bell tower that was found two kilometers away.

Every November 13, when the anniversary ceremony is held here, helicopters fly overhead and rain flowers down on the remains of Armero, a ghost town fading from memory.