Morne-Rouge, 1902
On the morning of May 8, 1902, Mount Pelée violently erupted. The incandescent pyroclastic flow swept down upon the city of Saint-Pierre, obliterating it completely within minutes. In contrast, on that exact same day, the village of Morne-Rouge was miraculously spared, even though it lay directly on the slopes of the volcano. This astonishing deliverance was accompanied by the apparition of Jesus and His Sacred Heart in the exposed Blessed Sacrament. On Ascension Thursday, Mount Pelée began erupting, hurling vast plumes of volcanic ash, toxic gases, and incandescent lava into the sky.

The inhabitants of Morne-Rouge, who harbored a fervent devotion to the Sacred Heart of Jesus, rushed immediately to their parish church to implore Our Lady of Deliverance to spare their village from imminent annihilation. Many beheld in the consecrated Host the Sacred Heart crowned with thorns. Others testified to seeing real Blood flowing from the Heart of Jesus. The mystical vision endured for many hours, and numerous parishioners begged for sacramental confession. The parish priest, Father Mary, imparted general absolution to all present, distributed Holy Communion, and exposed the Blessed Sacrament for public adoration.
During the adoration, a woman suddenly cried aloud: "The Sacred Heart of Jesus is inside the Host!". A multitude of people bore witness to the visible appearance of Jesus in the Host, revealing His Sacred Heart radiant with love. On May 8, the village of Morne-Rouge was completely preserved from the fiery destruction of the volcano, and this miraculous deliverance granted the entire population the grace to reconcile with God, frequent the sacraments, and live in the state of grace. On August 30 of that same year, a subsequent, even more massive eruption destroyed Morne-Rouge, finding the souls of its faithful prepared for eternity.
Source
Text and photographs: international exhibition «The Eucharistic Miracles of the World», by Saint Carlo Acutis. Original panel at miracolieucaristici.org.