The funeral chapel of the de las Alas family is located on the northern flank of the church of the Franciscan Fathers of Avilés. This area, adjacent to the medieval wall, was occupied by the town's cemetery until it was moved in 1813 to a meadow next to the now disappeared convent of La Merced. It was originally a free-standing, self-sufficient construction, and rivalled the parish church of San Nicolás in visual prominence from the estuary. Moreover, its funerary purpose, its spatial autonomy, its material ambition and, above all, the individual character of its promoter warn us of the emergence of a new mentality, less collective and more personal, which pursued the social consolidation of the client and his lineage.

In 1991 the chapel was declared an Asset of Cultural Interest.

From a structural point of view, the Alas chapel is a real novelty in the panorama of contemporary Asturian architecture. The building has a square floor plan, correct orientation and uses well-worked ashlar in the walls. This quality of material was very unusual and reveals the exceptional economic capacity of the promoter, who wished to show off to his fellow citizens.

As for the roof, it is undoubtedly the chapel's distinctive element, and its existence largely determines the rest of the structure. It is a dome-shaped vault reinforced by ribs. This type of roof, also known as Aquitanian, consists of a hemispherical frame arranged in concentric rows. The cross ribs start from very schematic faces at the corners of the building and cross over a keystone carved with the image of what appears to be the face of Christ. These ribs do not have the function of transmitting thrusts as in classical Gothic, but only act as reinforcements to help support thrusts resting directly on the walls.

As revealed by the research of Professor José María Azcárate, who published a fundamental study on Spanish Proto-Gothic constructions, the Aquitanian cupoliform models arrived on the Peninsula during the second half of the 12th century through the construction of Zamora Cathedral and then spread to Salamanca, Toro, Plasencia, Sahagún and parts of the Collegiate Church of Santillana del Mar.

Access to the interior of the chapel is through a simple doorway with a double archivolt framed by a plaster guard and supported by four columns beneath a modern coat of arms of the lineage. On the tympanum are arranged what appear to be winged heads of seraphim suggesting a trilobate. The capitals depict human heads in high relief, projecting towards the worshipper entering the enclosure. Since bearded individuals can be distinguished, it seems that they are male and female figures facing each other in pairs. All of them have a highly ornamental treatment of the hair, which sometimes appears to be covered with feathers or enhanced by diadems.

The coat of arms on the façade is a reproduction of the original, which is inside the chapel. It is not medieval, but from the modern period and displays the arms of the de las Alas family: a castle with three towers flanked by wings on waves of water and with an armed warrior at the door.

Precisely, the main function of the chapel of the Wings is to serve as a worthy tomb for Pedro Juan and his family. The location of the building, in the middle of the cemetery and close to the main chapel of the old Romanesque church, already ensured certain religious benefits, which were rounded off by the promoter with the foundation of a chaplaincy and the provision of masses for their souls. Inside, two tombs were placed under arches on either side of the chapel. The sepulchres on the epistle side correspond to two other arches on the outside of the enclosure.