The Church of the Theotokos of the Pharos was a chapel constructed in the eighth century in the midst of the Great Palace of Boukoleon in Constantinople (close to a lighthouse that gave the chapel its name) to house the instruments of Christ's Passion, which were soon joined by other celebrated items including the famous Mandylion of Edessa and numerous other relics. It is first attested in the entry of the Chronicle of Theophanes for the year 769 when it was the site of the wedding of Irene of Athens and Leo IV. After the end of Iconoclasm it was rededicated, an occasion which prompted Photios, who was patriarch at the time, to write a homily which offers us precious information regarding the church. In the intervening centuries, its collection of relics continued to grow, a fact attested by the itinerary of Anthony of Novgorod, as well as a list embedded in an account of the palace coup of John 'the Fat' Komnenos in 1200 authored by Nicholas Mesarites, who was skeuophylax of the church and was personally responsible for the care of its contents. During the sack of Constantinople during the Fourth Crusade, it avoided direct damage, and together with its contents was turned over into the care of the Latin Emperor Baldwin I. Nevertheless, the days of the Church of the Theotokos of the Pharos were numbered, and it presumably fell into disuse and ruin during the Latin occupation, as its contents were sold to fill the coffers of the beleaguered state. It is not attested in later sources. Relatively little can be ascertained regarding the form of the chapel save that it was small and extremely ornately decorated, features emphasized alike by Photios, Mesarites, Robert of Clari, and that it featured three apses, a central dome, and a narthex, suggesting that it, as restored in the 9th century, may have been an early example of the cross-in-square type. Moreover, given the Byzantine aesthetic predilection for intricate patterning and color, even the brief outlines which survive are suggestive to the historian's imagination, especially those that mention its impressive silver ciborium, its polychrome marble revetments, and the jewel-like opulence of its interior. Moreover, the appearance and especially the function of the chapel inspired that of La Sainte Chapelle (which would come to house much of the Pharos' former contents) as well as the Relic Chapel at Karlstejn.