The story of the visitation comes from Luke Chapter 1:39–45:
And Mary rising up in those days, went into the hill country with haste into a city of Juda. And she entered into the house of Zachary, and saluted Elizabeth. And it came to pass, that when Elizabeth heard the salutation of Mary, the infant leaped in her womb. And Elizabeth was filled with the Holy Ghost: And she cried out with a loud voice, and said: Blessed art thou among women, and blessed is the fruit of thy womb. And whence is this to me, that the mother of my Lord should come to me? For behold as soon as the voice of thy salutation sounded in my ears, the infant in my womb leaped for joy. And blessed art thou that hast believed, because those things shall be accomplished that were spoken to thee by the Lord.