"Union" or "Coronation" Cathedral, built between 1921 and 1922, sheltered various institutions: between 1922 and 1948 a military bishopric, between 1948 and 1975 a parish church, between 1975 and 1998 a bishopric, and since 1998 the Alba Iulia Archbishopric. It underwent repairs in 1994 and 2003. The museum collection conserves religious art items and rare books. The exhibits include religious items, rare books, priestly garbs, representing the history of the Orthodox Church in Transylvania.
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