Last month, part of a major wall came tumbling down in Pompeii, the ancient Roman city frozen in time by a first-century eruption of Mount Vesuvius. It was only the latest in a spate of collapses at the site, which experts say is in critical condition.

Though the site is said to be safe for tourists, the disintegration is alarming enough to have spurred the European Union to pledge 105 million euros (145 million dollars) for preservation.
© Roberto Salomone, AFP/Getty Images
The structural problems in Pompeii started with the collapse of a wall a year ago.

(Related: "Pompeiians Flash-Heated to Death - 'No Time to Suffocate.'")

Troubles at the World Heritage site, near modern Naples in southern Italy, began in earnest last year. In November 2010 Pompeii's Schola Armaturarum, a large building once used by gladiators for training, crumbled overnight due to water infiltration. Just a few weeks later, a 12-meter-long (13-yard) wall protecting a structure known as the House of the Moralist had fallen down in heavy rain.

Now that poor weather has returned, more trouble has followed. In late October, a portion of Pompeii's perimeter wall came apart.

Pompeii's "Situation Is Critical"

Last year, after the Schola Armaturarum had collapsed, UNESCO sent a team to inspect the site.

"The situation is critical," said Alix Barbet, an archaeologist at the French National Center for Scientific Research and a member of the Pompeii mission. "There is a lot to do."

According to UNESCO's report, the ruins' decay is exacerbated by excessive moisture and lack of routine maintenance. Inspectors are also concerned by the amount of ivy growth at the site.

"The backlog of maintenance needs to be tackled urgently," the report states. "Equally, drainage needs to be improved so that rain and groundwater are readily and rapidly removed to prevent the damage."

(See a picture of the baths of Pompeii.)

"What Pompeii's remains need is a continuous work of preservation, to counter the damage due to the elements," said ancient-Rome expert Filippo Coarelli, a former professor of archaeology at the University of Perugia.

"The archaeological site is very large: more than 40 hectares (nearly 100 acres) of streets, private houses, and public buildings," Coarelli said. Yet "today only five skilled workers take care of the whole site.

"The number is largely inadequate."

With the expected infusion of funds from the EU, Pompeii officials aim to improve those perceived inadequacies.

"We will monitor the state of preservation of the structures," said archaeological superintendent Teresa Elena Cinquantaquattro. "We'll secure the buildings in worst shape, we'll take steps to mitigate the damage from the elements, and finally we'll restore a number of houses and monuments."

(Watch video: Mount Vesuvius victims.)

The Tourists Keep Coming

Buried by Vesuvius in A.D. 79, the rich commercial town has been progressively excavated since the mid-18th century. The resulting frozen-in-time tableau has attracted travelers for centuries.

And despite Pompeii's recent collapses, tourists keep flocking to the site. "Their number is continuously growing. In 2010 they were more than 2.3 million," Cinquantaquattro said.

As archaeologist Coarelli noted, the small portion of the site open to the public is well maintained.

"Pompeii's troubles are out of view and the place is absolutely safe for tourists."

Three Pompeii-Area Must-Sees

1. Herculaneum: Smaller and better preserved then Pompeii, this ancient Roman holiday resort was also buried by Mount Vesuvius' A.D. 79 pyroclastic flows

2. Villa of Poppea: A home of Emperor Nero's second wife and another Vesuvius victim

3. Stabiae: Small port where naturalist Pliny the Elder died watching the A.D. 79 eruption