Michel Lamblin
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A beautiful Catholic church that dates back to the 15th century, and the site of a Marian apparition. You can access it by funicular, or there's some street parking near the funicular station - otherwise it's a bit of an uphill walk from Locarno (I think ~20min). Nice views of the lake, and very ornate decorations in the church, with a particularly nice oil painting from the 19th century of Jesus being carried from the cross.