According to lore, Mariazell was founded on 21 December 1157. After one of the first wooden "cells", the construction of a stone Romanesque chapel was begun in 1200 according to a building inscription over the main portal. The first documented mention of "cell" can be found in 1243.
In 1330, the church of Our Lady of Zell is documented in an indulgence certificate of the Salzburg Archbishop Frederick III as a much-visited place of pilgrimage and the place received the right to hold markets as early as 1344. The conferment of a complete indulgence by Pope Boniface IX in 1399 was of great importance for Mariazell. It was granted for the week after the octave of the Ascension of the Virgin Mary and led to the formation of penitential rites and processions, which remained lively even after the abolition of this indulgence and can be proved until the Baroque period. The flow of pilgrimages continued to increase.