Jasna Góra, as the main centre of religious life in our country, is at the same time a magnificent architectural complex, where every generation of Poles has left some kind of memento. The miraculous painting of Our Lady, venerated since 1382, has attracted crowds of pilgrims from all walks of life, who have left offerings according to their wealth and social status. The largest votive offering to the Mother of God is the altar financed by Jerzy Ossoliński, Great Chancellor of the Crown, in the years 1643-1650. This article presents details of the design and construction of the most valuable early altar in our country.