Juan de Melgar, who died in 1616, is buried in this chapel and endowed the chapel with 44 reales. The patronage of this, fell to the Dean and Chapter of the Cathedral of Segovia of which "according to the declaration of Don Miguel Rodríguez, sacristan of said church, a red chasuble, other white silk and a chalice are their own."
The chapel had an altar dedicated to the deceased's patron saint, Saint John the Baptist. The current altarpiece is made of stone and on it was the image of Our Lady of Lourdes. For a few years it has become the Chapel of the Columbariums presided over by the image of the Miraculous Virgin.
