A Govan Stone emerged from the earth.

(Image copyright) Tom Horne Three lost medieval tombstones have been rediscovered in a Scottish church yard.

The stones, carved with intricate interlaced patterns, were discovered by a 14-year-old boy during an archaeological survey of the old parish church of Govan, a medieval town that is now part of the city of Glasgow.

"I was just feeling around on the ground to see if there was anything there, and suddenly it made a sound and I realized I'd hit something," discoverer Mark McGettigan said in a statement.

[See photos of 'lost' medieval tombstones] Heritage Lost McGettigan found traces of Govan 1,000 years ago.

Today's Govan Old Parish Church stands on an ancient place of worship, St. Constantine's Church.

Archaeologists have discovered Christian artifacts at the site dating back to at least 500 AD, but Govan is best known for its carved stones, which date to between 800 AD and 1000 AD.

According to Govan Old Parish Church, the most impressive stones were carved early in this period.

It is a sarcophagus made from a single stone with the image of a warrior on horseback engraved on it.

Govan stone.

(Martin Shields/Govan Stones) In the centuries after the sarcophagi were made, local craftsmen continued the tradition of intricate carvings, creating stone crosses and long, sloping slabs of stone known as "hog's backs" that served as tombstones.

These craftsmen also carved flat stone slabs called cross-slates, which were placed on the surface of the tomb.

At the time of its engraving, Gavin was part of the Kingdom of Strathclyde, which lasted from about the 7th century until its conquest by the Scots in the 11th century.

Thirty-one Govan Stones have been discovered and preserved in the Parish Church Museum, but another 15 are thought to be lost forever.

In the 1970s, the shipyard wall next to the church was demolished and it is thought that the Govan stones that had not yet been brought indoors were crushed and carried away with the rubble.

Stones Unearthed Three Govan stones were discovered buried in a churchyard, suggesting that at least some of the missing stones survived.

McGettigan was volunteering on his first archaeological dig when he discovered the first stone.

The excavation is being carried out by charity Northlight Heritage, with funding coming from the City of Glasgow Regional City Deal and the Govan Cross Townscape Heritage initiative.

Stephen Driscoll, professor of historical archeology at the University of Glasgow and member of the Govan Heritage Trust, said in a statement: "(In photo: Stone monument discovered in Scotland)

"The Govan Stones are a collection of international importance and the discoveries of these stones reinforce the view of Govan as a major center of power in the early Middle Ages.

The three discovered stones were engraved with Celtic interlocking patterns and crosses and were very similar to those already on display in the church.

The stones are largely intact, albeit a little worn.

Tom Horn, an archaeologist and spokesman for Love Archeology, said no remains were found with the stones, which were moved around the cemetery and even recarved and reused over the centuries.

Archaeologists say they hope the finds mean more of the missing stones will survive.

Driscoll said the old parish church in Govan was currently being refurbished and the collection of stones would eventually get a brand new display.

Meanwhile, volunteers continue to search the old cemetery.

"I'm absolutely delighted," McGettigan said. In fact, I'm ecstatic about what I helped discover.

The 25 Most Mysterious Archaeological Discoveries on Earth 7 Bizarre Ancient Cultures Lost to History in Photos: Gladiator Tombs Originally published in LiveScience.