Written By: Ben Cosgrove

The walled, pint-sized city-state known as the Vatican physically takes up around 100 acres in the center of Rome, but occupies a measureless space in the lives of more than a billion practicing Catholics around the globe. Here, LIFE.com looks back to a time when the church was actively unearthing its own secrets . . . literally.

In 1950, LIFE reported on a years-long effort undertaken beneath the staggeringly ornate public realms of the Vatican, as teams of workers meticulously excavated the myriad tombs and other long-sealed, centuries-old chambers far underground. Nat Farbman’s color and black and white images in this gallery most of which never ran in LIFE, were touted on the cover of the March 27, 1950, issue of the magazine as “exclusive pictures” for the story titled “The Search for the Bones of St. Peter.”

Deep in the earth below the great basilica of St. Peter’s in Rome [LIFE wrote] the clink of pickaxes and the scrape of shovels in the hands of workmen have been echoing dimly for 10 years. In the utmost secrecy, they have penetrated into a pagan cemetery buried for 16 centuries. Architects feared they might disturb the foundations on which rests the world’s largest church. But the workmen, with careful hands, pushed forward finally to the area where, according to a basic tenet of the Catholic Church, the bones of St. Peter were buried about A.D. 66.

The Church has always held that Peter was buried in a pagan cemetery on Vatican Hill. Now, for the first time, there is archaeological evidence to support this: the newly discovered tombs, which LIFE shows [in these exclusive pictures].

The greatest secret of all—whether the relics of the Chief Apostle himself were actually found —s one which the Vatican reserves for itself, although there have been rumors that the discovery of the relics will be announced at an appropriate time during the Holy Year.

In the end, LIFE’s editors expressed their appreciation for “the privilege of guiding LIFE’s readers through these chambers where in the dust of antiquity can be traced the humble yet transcendent beginnings of the Christian faith.”

[MORE: Buy the LIFE book, Pope Francis: The Vicar of Christ, From Saint Peter to Today.]

NOTE: In December 1950 Pope Pius XII announced that bones discovered during the excavation could not conclusively be said to be Peter’s. Two decades later, in 1968, Pope Paul VI announced that other bones unearthed beneath the basilica—discovered in a marble-lined repository, covered with a gold and purple cloth and belonging to a man around 5′ 6″ tall who had likely died between the ages of 65 and 70—were, in the judgment of “the talented and prudent people” in charge of the dig, indeed St. Peter’s.

To this day, that claim has as many doubters as adherents.

 

Liz Ronk edited this gallery for LIFE.com. Follow her on Twitter at @LizabethRonk.

In a clutter of bones and artifacts the foreman of a team of Vatican workmen examines an ancient archway, St. Peter's, Rome, 1950.

In a clutter of bones and artifacts the foreman of a team of Vatican workmen examined an ancient archway, St. Peter’s, Rome, 1950.

Nat Farbman The LIFE Picture Collection/Getty Images

The interior of St. Peter's basilica, with markers indicating the location of the excavation beneath the floor, 1950.

The interior of St. Peter’s basilica, with markers indicating the location of the excavation beneath the floor, 1950.

Nat Farbman The LIFE Picture Collection/Getty Images

The tomb of the Caetennii (17 x 18 feet) was one of the richest and most lavishly decorated of all those excavated beneath St. Peter's.

The tomb of the Caetennii (17 x 18 feet) was one of the richest and most lavishly decorated of all those excavated beneath St. Peter’s.

Nat Farbman The LIFE Picture Collection/Getty Images

Tomb of the Egizio featuring elaborate sarcophagi sculpted with scenes of Bacchic rites. While most of the findings here were purely pagan, there were also Christian designs -- for example, of a palm leaf and a dove.

The Tomb of the Egizio featured elaborate sarcophagi sculpted with scenes of Bacchic rites. While most of the findings here were purely pagan, there were also Christian designs—for example, of a palm leaf and a dove.

Nat Farbman The LIFE Picture Collection/Getty Images

Scene during the excavation beneath St. Peter's in Rome, 1950.

Scene during the excavation beneath St. Peter’s in Rome, 1950.

Nat Farbman The LIFE Picture Collection/Getty Images

The hunt of the Amazons is portrayed on a polychrome mosaic decorating the facade of the tomb of the Marci.

The hunt of the Amazons was portrayed on a polychrome mosaic decorating the facade of the tomb of the Marci.

Nat Farbman The LIFE Picture Collection/Getty Images

Scene during the excavation beneath St. Peter's in Rome, 1950.

Scene during the excavation beneath St. Peter’s in Rome, 1950.

Nat Farbman The LIFE Picture Collection/Getty Images

A workman cleans an inscription during the excavation beneath St. Peter's in Rome, 1950.

A workman cleaned an inscription during the excavation beneath St. Peter’s in Rome, 1950.

Nat Farbman The LIFE Picture Collection/Getty Images

Pope Pius XI, whose desire to be buried below St. Peter's nave led to the historic excavations, lies in his stone sarcophagus in renovated upper grottoes.

Pope Pius XI, whose desire to be buried below St. Peter’s nave led to the historic excavations, lay in his stone sarcophagus in renovated upper grottoes.

Nat Farbman The LIFE Picture Collection/Getty Images

The oldest burial chamber found during the excavation beneath St. Peter's in Rome, 1950.

The oldest burial chamber found during the excavation beneath St. Peter’s in Rome, 1950.

Nat Farbman The LIFE Picture Collection/Getty Images

Scene during the excavation beneath St. Peter's in Rome, 1950.

Scene during the excavation beneath St. Peter’s in Rome, 1950.

Nat Farbman The LIFE Picture Collection/Getty Images

Workmen examining underneath the floor of Basilico.

Workmen examined underneath the floor of the Basilico.

Nat Farbman The LIFE Picture Collection/Getty Images

Workers gauge damage from water seepage during the excavation beneath St. Peter's in Rome, 1950.

Workers gauged damage from water seepage during the excavation beneath St. Peter’s in Rome, 1950.

Nat Farbman The LIFE Picture Collection/Getty Images

Gauging damage from water seepage during the excavation beneath St. Peter's in Rome, 1950.

Workmen gauged damage from water seepage during the excavation beneath St. Peter’s in Rome, 1950.

Nat Farbman The LIFE Picture Collection/Getty Images

The oldest burial chamber found during the excavation beneath St. Peter's in Rome, 1950.

The oldest burial chamber found during the excavation beneath St. Peter’s in Rome, 1950.

Nat Farbman The LIFE Picture Collection/Getty Images

A double row of burial chambers beneath St. Peter's, 1950.

A double row of burial chambers beneath St. Peter’s, 1950.

Nat Farbman The LIFE Picture Collection/Getty Images

Inscription revealed during the excavation beneath St. Peter's in Rome, 1950.

An inscription revealed during the excavation beneath St. Peter’s in Rome, 1950.

Nat Farbman The LIFE Picture Collection/Getty Images

An early Christian mosaic, possibly the earliest known, decorates the ceiling and walls of a mausoleum close to area where St. Peter is supposed to have been buried, Rome, 1950.

An early Christian mosaic, possibly the earliest known, decorated the ceiling and walls of a mausoleum close to area where St. Peter is supposed to have been buried, Rome, 1950.

Nat Farbman The LIFE Picture Collection/Getty Images

Rich polychrome stucco work in the southwest corner of the Tomb of the Caetennii shows how resplendently it was decorated.

Rich polychrome stucco work in the southwest corner of the Tomb of the Caetennii showed how resplendently it was decorated.

Nat Farbman The LIFE Picture Collection/Getty Images

Classic sculpture adorns the Marci sarcophagus of Q. Marcius Hermes and his wife.

Classic sculpture adorned the Marci sarcophagus of Q. Marcius Hermes and his wife.

Nat Farbman The LIFE Picture Collection/Getty Images

Scene during the excavation beneath St. Peter's in Rome, 1950.

Scene during the excavation beneath St. Peter’s in Rome, 1950.

Nat Farbman The LIFE Picture Collection/Getty Images

Foreman of work crew, photographed during the excavation beneath St. Peter's in Rome, 1950.

The foreman of work crew posed during the excavation beneath St. Peter’s in Rome, 1950.

Nat Farbman The LIFE Picture Collection/Getty Images

The tomb of Pope Boniface VIII, beneath the Vatican, photographed in 1950.

The tomb of Pope Boniface VIII, beneath the Vatican, photographed in 1950.

Nat Farbman The LIFE Picture Collection/Getty Images

Scene during the excavation beneath St. Peter's in Rome, 1950.

Scene during the excavation beneath St. Peter’s in Rome, 1950.

Nat Farbman The LIFE Picture Collection/Getty Images

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