Today the Ukrainian Orthodox Church commemorates one of the best-known icons of Rus', the Pochayiv Icon of the Pochayiv Lavra of the Dormition. The lavra was founded as a monastery in 1340 by two monks and has been associated closely with the Mother of God since its founding as she appeared to the monks and a herdsman on a nearby hilltop, leaving behind an imprint of her foot on one of the hilltop's rocks.
In 1559 a traveling Constantinopolitan Orthodox metropolitan visiting Volhynia gave a local noblewoman an icon of the Mother of God from Constantinople as a memento of his stay in the region. In time a radiance was noticed to be coming from the icon, and in 1597 the noblewoman's brother was healed by the icon, after which it was given in thanksgiving to the Pochayiv Monastery, which enshrined it in the Church of the Dormition.
This icon, the Pochayiv Icon, has remained at the Pochayiv Lavra for 414 years and has been glorified by many miracles. In 1675 the icon saved Pochayiv from invading Tatars, who saw the Mother of God together with angels brandishing swords and St. Job of Pochayiv over the Church of the Dormition as they prepared for their final assault on the lavra. As a result the Tatars fled, while others who were captured embraced Orthodoxy and even the monastic life.
The icon remains a treasured relic of the Pochayiv Lavra alongside the Mother of God's footprint and is kept in the lavra's Cathedral of the Dormition to this day.
Information from Musings from the Fourth Rome: A Source for Orthodox Christian News and Events