The Palace of Pena Chapel resulted from the adaptation of the former Monastery Church of Our Lady of Pena.
Up until the abolition of religious orders, this church was open to the faithful (who would arrive at the Pena monastery along the Pilgrims Way), even while not holding any role as a parish church.
The main altar retable from the former church, in alabaster and limestone from the Sintra region, was worked on between 1529 and 1532, by the sculptor of French origin, Nicolas de Chanterenne, and resulted from a commission from João III, son of Manuel I, the founder of the convent.
A particular highlight is the stained glass window installed by Ferdinand II in the wall opposite the main altar, which dates to 1840, shortly after the Palace began construction, which was produced by the famous stained glass workshop in Nuremberg belonging to the Kellner family. The glass reveals artistic intentions but also the political legitimacy underlying the construction of the Palace.