30 km south of Baghdad, on the banks of the Tigris, the ark also known as Taq Kasra dates from the sixth century.

Erected where the capital of the Persian dynasty of the Sassanids was located, the ocher brick vault rises to 37 meters and is part of the remains of a palace.

In 2013, sections of the elliptical vault of Taq Kasrides were reconstructed with new bricks.

After rains in 2020, some have started to fall.

"What is falling right now is not the original Sassanid construction, it is modern repairs," David Michelmore, conservation expert who collaborates with a team of archaeologists from the American PENN University, told AFP. .

A photo taken on November 24, 2021 shows the huge crack in Iraq's Ctesiphon Arch, the world's largest brick arch, 1,400 years old Sabah ARAR AFP

"We will have to dismantle the work done in 2013 (...) it has destabilized the structure," he added.

With his team, Michelmore is thus leading a first phase of renovation described as "emergency intervention", launched in March and which should end in December.

The work aims to "consolidate" the site, Iraqi Minister of Culture and Antiquities Hassan Nazem told AFP, also referring to "studies on the nature of the soil and foundations".

The site being near the river, it underlines the "danger" of the underground infiltrations.

"Many errors"

Today, the monumental arch stands in the middle of palm groves near the town of Madain.

It is flanked on either side by two imposing facades, decorated with colonnades and vaulted niches, also in brick.

Photo taken on November 24, 2021 shows a side view of the Arch of Ctesiphon, the world's largest brick arch at 1,400 years old, in Madain, south of Baghdad Sabah ARAR AFP

This first phase is funded with a budget of $ 700,000 from the International Alliance for the Protection of Heritage in Conflict Areas (ALIPH), indicates the director of the Council of Antiquities and Heritage Laith Majid Hussein.

According to him, the next phase will consist of a "total restoration" which should make it possible to consolidate the structure and prevent collapses.

He also deplores the "many errors" of the people who carried out the previous work, who in particular put a large "layer of cement on the arch".

On several occasions already, the authorities have sounded the alarm bells concerning the state of the site.

As early as 2004, cracks had appeared on the elliptical vault, caused by infiltration of rainwater.

Workers in Iraq on scaffolding erected for the restoration of the arch of Ctesiphon, the largest brick arch in the world 1,400 years old, in Madain, south of Baghdad, November 24, 2021 Sabah ARAR AFP

Mr. Michelmore recalls that the ark was built in 540. “It is almost exactly the same age as (the church) Hagia Sophia in Constantinople (Istanbul). Both monuments are very innovative in terms of size and design. ambition, "he enthuses.

© 2021 AFP