The story for which Helena is best remembered, the inventio crucis, or Finding of the True Cross, is later than her lifetime and legendary in its detail. In its developed form it relates that at Jerusalem Helena had the site of Golgotha excavated, uncovered three buried crosses, and identified the true one when a touch of it healed a sick or dead person, thereby recovering the Cross of Christ along with the nails and the titulus.
The tradition first surfaces at the very end of the fourth century. Ambrose of Milan, in a funeral oration of 395, some sixty-five years after Helena's death, is the earliest writer to credit her with the finding. Slightly later church historians, Rufinus, Gelasius of Caesarea and others, elaborate it, and from them it passed into universal medieval belief and into collections such as the Golden Legend.
Modern scholarship, following studies such as Jan Willem Drijvers's, distinguishes sharply between the historical pilgrim and the legendary discoverer. That some cult of relics of the Cross grew at Jerusalem in the fourth century is likely; that Helena personally found the Cross is a legend that attached her prestigious name to those relics a couple of generations after she died. The atlas dates the tradition to its late-fourth-century sources and labels it as legend, not history.