Attracted by their reputation for holiness, several young men soon joined Romanus and Lupicinus, who founded their first monastery in Condat; but this soon proved too small to accommodate all the aspiring monks. They built another monastery in Lauconne (today's Saint-Lupicin), leading together their confréres to the service of God by making a virtuous agreement for their different characters: Romanus was more forgiving and mild, while Lupicinus was more demanding in the observance of monastic discipline. If laxism spread in a monastery, Lupicinus intervened; if instead there was too much rigour, Romanus would intervene. The two Saints were then joined by their sister Yole, and for her they built a women's house on an overhanging rock, in an area later called Saint-Romain-de-Roche, which would later host over one hundred nuns.
Around the year 450, on the eastern side of the Jura Mountains, Romanus founded the first monastery in Switzerland, later called Romainmôtier, whose monastic function ceased in 1537, when the Protestant Reformation brought about its secularisation and the destruction of the cloister. Saint Romanus' most famous miracle occurred during a pilgrimage to the tomb of Saint Maurice. One night, near Geneva, the Saint took shelter with two lepers who lived in a hut, where he comforted and embraced them. Upon awakening, the two realised that they had completely healed and went to the city to tell the incident to the Genevans.
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