Which Byzantine monastery in Phocis is famous for its katholikon mosaics?

Hosios Loukas in Phocis is famous for the mosaics of its katholikon.

The monastery lies near Distomo in central Greece and is dedicated to Saint Luke of Steiris, an ascetic who lived in the tenth century. Its principal church was built in the eleventh century and is one of the finest surviving monuments of middle Byzantine architecture.

The katholikon uses a domed, cross-in-square composition and contains marble revetment, mosaics, and painted decoration. Its imagery includes Christological scenes and portraits of saints arranged according to the liturgical and architectural spaces.

Hosios Loukas forms part of a UNESCO World Heritage grouping with the monasteries of Daphni and Nea Moni of Chios. Those sites share important examples of Byzantine religious art, but each has a distinct architectural history and decorative program.