Wait, what? Well, for one, we have photographs of the crowd making their way and assembling at the Cova da Iria (a grazing field for cattle and the cite of the apparitions). From these several photographs, modern scholars have estimated the crowd to have been near 100,000 in size. A dozen or so journalists from Portugal’s largest newspapers were at the scene, and it was these same anti-theistic journalists (the most prominent was a Free Mason, a historical enemy of the Catholic Church

) who reported on the apparitions with derision, mockery, and incitement of violence up until that point. From the crowds themselves, we have hundreds and hundreds of letters they wrote to confidants and investigators at the time. We also have the books of a handful of investigators who spent years in Fatima interviewing the witnesses and the authorities.
We also have the newspaper articles leading up to the event which reported on the apparitions and the October 13 prediction by the Blessed Virgin via the children. The prediction, by the way, was made by as early as May 13, 1917.
What else can I tell you? On July 13, 1917, when the Blessed Virgin told two of the children that they were to die soon (and they
did die soon, exactly a year from October 13, the last apparition, and the youngest is on record for predicting the exact date and time and nature of her death), the two children ecstatically talked about their impending deaths to baffled pilgrims and villagers. Mind you, the children were ages 9 and 7 at this time. I mean, so far, we’ve only been talking about the Miracle of the Sun, but I, personally, find the witness of the children to be far more compelling. For example, on the August 13, 1917 apparition, they were kidnapped by the administrator of the region, and we have records of their unjust arrest. They were placed in a cell with adult prisoners, male, and with no adult supervision or a lawyer present. They were threatened with gruesome death, but none of them recanted the apparitions. Again, these children ages 10, 9, and 7.