In new excavations centered around the Chapel Royal of St Peter ad Vincula on the grounds of the Tower of London, archaeologists have uncovered more than 20 previously unknown burials.

Following a trial pit dug in 2019, this is the first major archaeological excavation at the historic site in three decades and the first ever in this section of the grounds, according to Historic Royal Palaces, the independent charity that cares for the monument.

"Undertaking these two excavations," says Alfred Hawkins, Curator of Historic Buildings at Historic Royal Palaces, "has provided us with a generational opportunity to enhance our understanding of the evolution of the Chapel of Saint Peter ad Vincula, and the buildings which stood before it."

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A visitor map of the Tower of London grounds, with a yellow arrow pointing to the location of the Chapel Royal of St Peter ad Vincula. (Historic Royal Palaces)

During its millennium-long history, the Tower of London has served, variously, as a prison complex that housed royalty, a palace, and a fortress for the protection of the Crown Jewels. Today the Tower is a tourist destination, but many secrets still lie beneath its grounds.

Many of them are likely to remain there, but the commissioning of a new elevator to improve visitor access to the 500-year-old chapel has afforded a rare opportunity.

In the UK, any major construction work is legally required to be preceded by an archaeological assessment to protect and preserve the island's ancient history. In 2019, archaeologists made an experimental foray outside the chapel, a dig that yielded the remains of two individuals who were likely members of the Tower's community during the 16th century CE.

Earlier this year, archaeological firm Pre-Construct Archaeology commenced the major work outside the chapel, which has so far yielded the remains of more than 20 individuals. Those remains include a cluster of 14th-century individuals who may have been interred as part of a plague burial.

Four other burials, from the 12th or 13th century, were interred in coffins, which was highly unusual for the period and may indicate that the individuals were of a high status.

And some rare grave goods have been found, too, including textile from a shroud, which usually succumbs to decay, and pots containing charcoal, a type of grave good known from only one other medieval English burial.

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The archaeologists have also found evidence of the history of the site itself, including the charred remnants of an earlier version of the chapel, built by Edward I in the 1280s, which burned down in 1512. Below that, a layer of stone suggests that even earlier work may have taken place at the site, perhaps during Henry III's rebuilding in 1240.

The work is ongoing, so more burials may be uncovered before the researchers are done. Then follows the painstaking work of analyzing the remains to learn about who they were and why they died.

"We're already gaining insight into the residents of the Tower in a way we have never been able to do before," says Jane Sidell, archaeologist at the Historic England organization.

"But this is just the tip of the iceberg – there is so much more to learn through further analysis about the people as well as the buildings of one of England's most evocative historic monuments."