Under the blessing of His Eminence, the Patriarchal Exarch of Western Europe, Metropolitan of Corsun and Western Europe, Nestor, an annual pilgrimage to the Basilica of Notre-Dame-de-Bonne-Garde (Our Lady of Good Guardian) will take place on September 23. This basilica, situated in Longpont-sur-Orge near Paris, houses one of the most extensive collections of relics and sacred items from the undivided Church in France, as reported by the Corsun Diocese's website. Pilgrims will have the opportunity to participate in Orthodox Liturgy.

Beneath the arches of this ancient basilica, located along the pilgrimage route to the relics of Saint James the Apostle in Compostela, lie approximately 1,500 Christian relics. Among these treasures are a part of the Life-Giving Tree of the Lord's Cross, relics of Saint Peter the Apostle, Saint Anna the Righteous, the holy Unmercenaries and Healers Cosmas and Damian, the holy Martyrs Margarita, Barbara, Agafia, Vera, Nadezhda, Lyubov, and Sofia, Parisian Saints of God: Hieromartyrs Herman and Marcel of Paris, and Righteous Geneva, along with many other saints from the undivided Church. The "Mother of God – The Good Guardian" church has been a renowned place of pilgrimage since the 8th century.

The site where the present-day church has stood since the 12th century is one of the early centers of Christianity in this region. According to legend, the Gallic tribes residing on the hill by the Org River were among the first to be enlightened by Saint Dionysius, the first Bishop of Paris.