This unique sculptural ensemble is a monumental work whose exhibition, due to its technical characteristics, is unusual in a museum.

This portal - Romanesque from the second half of the 13th century - belonged to one of the two churches whose remains are still preserved today in the place called farm or castle of Anzano, in Huesca.

The portal is formed by four archivolts in gradation that are decorated with different motifs based on cylinders and plant themes.

The tympanum identifies the central figure, known as Our Lady of Milk, under a canopy held by two angels. She appears crowned and enthroned with the child on her lap. To the left is a seated male figure, which could be Saint Joseph or a prophet; and, to the right, a female figure, perhaps a prophetess or sibyl. What draws the most attention from the whole is the disproportion that can be seen in the figures with respect to themselves and of each other. In the Romanesque period the size of the characters was represented in relation to their hierarchy.

From a stylistic point of view, this portal is related to the door  of the Godchildren  of the Seu Vella de Lleida, a model that spread throughout the immediate territory from the beginning of the 13th century.