One of these events necessitated the construction of an international airport in Knock, Ireland, which only has about 1,000 residents.
A non-Russian movement known as the Blue Army formed in response to one of these events. After one of these events, Catherine Labouré created a golden medallion that depicts the letter "M" above two hearts, one of which is impaled by a sword. One of these events necessitated the construction of an international airport in Knock, Ireland, which only has about 1,000 residents. Tepeyac Hill was where (*) Juan Diego witnessed one of these events. Lúcia Santos and her two cousins were told "three secrets" during these events, which may have predicted Mehmet Ali Agca's assassination attempt. Because of one of these events, the town of Lourdes is visited by six million pilgrims each year. For 10 points, identify these events in which the Virgin mother of Christ appears supernaturally.
A non-Russian movement known as the Blue Army formed in response to one of these events.
Marian apparitions [or: obvious equivalents, such as appearances of the Virgin Mary; prompt on: answers that mention Our Lady]