When Mary fled to Egypt to escape Herod, she needed to stop to feed the baby Jesus, and when she did so, milk fell from her breast and turned the stone white. So runs the story attached to the white rock at this site, close by the Church of the Nativity.
On entering you find yourself in a cave, the white rock marked by centuries of pilgrims desperate for its healing properties. Breastfeeding rates vary by time and place, but the problems women face with it are similar, not least a lack of milk production. Consume even a morsel of this rock, however, and you are setting yourself up for success. The result is a grotto that has become a shrine for prayer, with ground rock available for purchase.
Attended to by the Sisters of Perpetual Adoration, there is constantly someone in prayer before the Blessed Sacrament. This bit of the building may feel new, but the continuous prayer is a long tradition. This Catholic church was opened in 1872.
Further upstairs is a congregational church, where Mass is celebrated regularly. Bethlehem may be a site of pilgrimage for tourists, but it remains a modern city too, with the routine of daily life, including worship.
The more gruesome history of the place marks it as the site of the burial of the children murdered by Herod (the Murder of the Innocents) when he was trying to kill the baby Jesus. The Milk Grotto is an unusual church, but definitely one worth stopping at if you are visiting Bethlehem. It is only around the corner from the Church of the Nativity, after all.