At the end of the eleventh century, monks at Cluny commissioned the largest basilica in Christendom. Much has been written about the mother church of the Cluniac Order, with a focus on reconstructing missing parts of the church and making connections between Cluniac architecture and medieval culture. My approach is different in a number of ways — concentrating on the innovative and refined features of the surviving transept and placing them in a complex artistic context. It combines examination of archaeology, architecture and sculpture, interweaves analysis of aesthetics — light, space, articulation and decoration — with analysis of practicalities — function, construction and structure, and uncovers numerous sources of the building, piecing together influences from multiple directions. The photography is inclusive as well, documenting from various angles and distances, under different lighting conditions, the power and nuance of the monument.