Conservation experts and archaeologists are uncovering new details about the tomb of Emperor Otto I while carrying out an extensive restoration project at Magdeburg Cathedral.

Since January 2025, the Saxony-Anhalt Cultural Foundation and the State Office for Heritage Management and Archaeology have led efforts to preserve the heavily damaged burial site of Otto the Great, the 10th-century ruler who laid the foundations of the Holy Roman Empire.

Excavations uncover clues to the tomb’s history

The relocation of the sarcophagus also allowed archaeologists to investigate its foundation for the first time. Excavations revealed large sandstone blocks beneath the tomb, including reused building stones marked by late medieval stonemasons. The findings suggest that the sarcophagus was moved several times over the centuries.

Excavations produced numerous artifacts, including coins, glass beads, ceramics, roof tiles, clothing pins, and fragments of painted plaster from earlier cathedral structures. Researchers also uncovered a lead bullet beneath the floor, reflecting Magdeburg’s turbulent history.

Archaeologists restoring the tomb of Emperor Otto I in Magdeburg Cathedral have uncovered medieval foundations, underground passages and centuries-old artifacts. pic.twitter.com/B1PNeRTlwq

— Tom Marvolo Riddle (@tom_riddle2025) June 12, 2026

Researchers also uncovered layers of rubble linked to medieval and early modern construction activities in the cathedral’s High Choir. A network of underground passages, some possibly dating to the Middle Ages, was also documented.

Despite the discoveries, archaeologists found no evidence showing whether Otto I’s tomb occupied the same location in an earlier cathedral that once stood on the site. The original placement of the emperor’s burial, therefore, remains uncertain.

Damage prompted conservation efforts

Otto I, who was crowned emperor in 962, established one of medieval Europe’s most powerful empires. His tomb in Magdeburg Cathedral is considered one of Germany’s most important medieval monuments.

The project began after routine inspections in 2024 revealed serious deterioration in the emperor’s tomb. Researchers identified several threats to the monument, including corroded iron fittings, rising moisture from the ground, and fluctuating humidity levels inside the cathedral.

Scientific analyses confirm the emperor’s remains

As part of the conservation work, experts carried out extensive non-invasive documentation of the sarcophagus and its surroundings. The marble cover slab, weighing about 300 kilograms (660 pounds), was removed so researchers could examine the damaged wooden coffin inside.

Anthropological and genetic analyses later confirmed that the human remains belonged to Otto I, supporting centuries-old historical accounts of his burial at the cathedral.

The emperor’s remains are scheduled to be reinterred on Sept. 1, 2026, in a newly designed coffin currently being created through a competition organized by the Saxony-Anhalt Art Foundation.

Restoration work addresses long-term damage

To protect the monument for the future, conservation teams moved the limestone sarcophagus from its original location in early 2026 using a specially designed transport structure. The sarcophagus now sits inside a secure enclosure within the cathedral, where restoration work is underway.

Specialists are removing corroded iron nails and clamps, many believed to date to the 19th century. As the metal rusted over time, it expanded and placed pressure on the stone, increasing the risk of cracking. Conservators are also removing harmful iron residues from the marble cover slab.

Cathedral remains open during conservation work

Church services continue as normal during the project, while visitors can still view major features of the cathedral, including the High Choir and its famous 13th-century sculptures. Officials said the public will continue to receive updates as restoration and research progress.

Leo called Gaudí's unfinished temple, one of the world's most visited monuments, a "sign of unity and harmony for all of Spain," an ongoing building project like the lifelong journey all Christians make to find God.

Tourists stand in line under the summer sun outside Notre Dame Cathedral, waiting to climb the landmark and see its famous Roman artifacts. Just a few meters below them, archaeologists are digging into nearly 2,000 years of Parisian history.

The excavation is taking place beneath the cathedral’s forecourt as part of a project to redesign the square. Paris plans to add trees, shade, and cooling features around Notre Dame following its restoration after the devastating 2019 fire. Before work can begin, archaeologists must investigate and protect any remains buried underground.

French media have dubbed the project the “dig of the century” because of the discoveries emerging from one of the city’s most historic locations.

“It’s a rare opportunity for us to work on something that’s tangibly going to make a difference to the history of Paris,” Lucie Altenburg, a conservator with the Paris archaeology unit, told The Associated Press.

Ancient artifacts emerge

Researchers have already recovered hundreds of artifacts. One of the most important finds is a fourth-century coin depicting Roman Emperor Constantine. The coin was heavily corroded when it was unearthed, but X-ray imaging revealed the emperor’s portrait. Such finds help archaeologists date the different occupation layers beneath the cathedral.

The team has also uncovered fragments of medieval pottery marked with faint reddish inscriptions painted on the inside. Similar symbols appear on multiple shards, but experts have not yet determined their meaning.

Archaeologists digging beneath Notre Dame Cathedral have uncovered Roman-era artifacts, medieval pottery with mysterious markings and evidence of Paris' ancient past.#notredame #romanartifacts pic.twitter.com/NB7zlQJtGq

— Tom Marvolo Riddle (@tom_riddle2025) June 3, 2026

Some of the most remarkable discoveries have come from medieval latrines buried beneath houses that once crowded the area around Notre Dame. The pits served as both toilets and rubbish dumps, creating conditions that preserved everyday objects for centuries.

Archaeologists have recovered complete jugs, cups, and other ceramics that survived intact after spending hundreds of years underground. It is “rare to find complete ceramics,” said archaeologist Valentine Breloux.

Clues to Paris’ evolution

The excavation has also revealed evidence of Paris’ transformation from the Roman city of Lutetia into the medieval capital that followed.

Archaeologists discovered a Roman stone doorstep that had been removed from a larger building, turned upside down, and reused as paving in a later roadway. The find shows how residents repurposed materials as the Roman world gave way to a new era.

Once artifacts leave the site, they are transported to the city’s archaeology center, where specialists clean, catalog, and study them.

Looking deeper into the past

The work is expected to continue as Paris moves forward with plans to plant 160 trees and create a cooler, greener public square by 2028. Archaeologists hope to dig even deeper before then, searching for traces of the Gauls, the people who inhabited the area before the Roman conquest.

“The hope is that we are able to go back in time even further than we’ve ever been before,” Altenburg said.