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Holy Trinity, Feast of, (Trinity Sunday), Catholic feast introduced in 1334 for the whole church (1st Sunday after Pentecost). The Feast celebrates the dogma of the Trinity of God. Austria has more than 30 pilgrimage churches (e.g. Sonntagberg, Lower Austria) and numerous commemorative columns in celebration of the Holy Trinity (Plague Monuments).
Literature: A. Adam and R. Berger, Pastoralliturgisches Handlexikon, 1980.