Helena, the emperor (Constantine's) mother...

–from whose name having made Drepanum, once a village, a city, the emperor called it Helenopolis– being divinely directed by dreams went to Jerusalem. Finding that which was once Jerusalem, desolate “as a Preserve for autumnal fruits,” according to the prophet, she sought carefully the sepulchre of Christ, from which he arose after his burial; and after much difficulty, by God’s help she discovered it. What the cause of the difficulty was I will explain in a few words.

Those who embraced the Christian faith, after the period of his passion, greatly venerated this tomb; but those who hated Christianity, having covered the spot with a mound of earth, erected on it a temple to Venus, and set up her image there, not caring for the memory of the place. This succeeded for a long time; and it became known to the emperor’s mother. Accordingly she having caused the statue to be thrown down, the earth to be removed, and the ground entirely cleared, found three crosses in the sepulchre: one of these was that blessed cross on which Christ had hung, the other two were those on which the two thieves that were crucified with him had died. With these was also found the tablet of Pilate, on which he had inscribed in various characters, that the Christ who was crucified was king of the Jews. Since, however, it was doubtful which was the cross they were in search of, the emperor’s mother was not a little distressed; but from this trouble the bishop of Jerusalem, Macarius, shortly relieved her. And he solved the doubt by faith, for he sought a sign from God and obtained it.

The sign was this: a certain woman of the neighborhood, who had been long afflicted with disease, was now just at the point of death; the bishop therefore arranged it so that each of the crosses should be brought to the dying woman, believing that she would be healed on touching the precious cross. Nor was he disappointed in his expectation: for the two crosses having been applied which were not the Lord’s, the woman still continued in a dying state; but when the third, which was the true cross, touched her, she was immediately healed, and recovered her former strength. In this manner then was the genuine cross discovered.

The emperor’s mother erected over the place of the sepulchre a magnificent church, and named it New Jerusalem, having built it facing that old and deserted city. There she left a portion of the cross, enclosed in a silver case, as a memorial to those who might wish to see it: the other part she sent to the emperor, who being persuaded that the city would be perfectly secure where that relic should be preserved, privately enclosed it in his own statue, which stands on a large column of porphyry in the forum called Constantine’s at Constantinople.

I have written this from report indeed; but almost all the inhabitants of Constantinople affirm that it is true. Moreover the nails with which Christ’s hands were fastened to the cross (for his mother having found these also in the sepulchre had sent them) Constantine took and had made into bridle-bits and a helmet, which he used in his military expeditions. The emperor supplied all materials for the construction of the churches, and wrote to Macarius the bishop to expedite these edifices. When the emperor’s mother had completed the New Jerusalem, she reared another church not at all inferior, over the cave at Bethlehem where Christ was born according to the flesh: nor did she stop here, but built a third on the mount of his Ascension. So devoutly was she affected in these matters, that she would pray in the company of women; and inviting the virgins enrolled in the register of the churches to a repast, serving them herself, she brought the dishes to table. She was also very munificent to the churches and to the poor; and having lived a life of piety, she died when about eighty years old. Her remains were conveyed to New Rome, the capital, and deposited in the imperial sepulchres. 

Socrates Scholasticus, Historia Ecclesiastica 1.17