When King Olaf Haraldsson gave up the old Viking gods to become Norway’s first Christian ruler, he fundamentally changed his society. Part of that legacy is the church he built in his capital city of Nidaros (now known as Trondheim), which was recently discovered at the construction site of a new office building. The church’s stone foundation is remarkably intact. According to Anna Petersén of the Norwegian Institute for Cultural Heritage Research, the nave, choir, entrances, and foundation of the altar are still in place. The church was dedicated to Saint Clements the patron of slaves and seafarers and a popular figure among observant Norse raiders. A series of radiocarbon dates shows that the church was built in the early eleventh century, which affirms historical descriptions.

Researchers also found a construction behind the altar that they are calling the “Pall,” the place where they believe Haraldsson was laid to rest after he was martyred in the Battle of Stiklestad in 1030. Petersén says the church became such a popular pilgrimage site that the king’s coffin was later removed to a larger cathedral. The discovery of Haraldsson’s old church gives the research team an opportunity to reconstruct the royal compound and the city’s religious landscape at a time of profound spiritual change.