Alejas iela 2, Dagda, +371 25727379, dean Pāvels Odiņš (+371 29583026).
An architectural monument of national importance. Built in 1741 in Corinthian baroque style. It has 6 ornate altars including three luxurious brick wall altars with cornices and pilasters. Great altar includes two paintings – “St. Trinity” and “In Honor of The Virgin Mary of The Immaculate Conception”.