Dome

View of the altar; The last known example of an ambulatory basilica is S Agnese fuori le mura on the Via Nomentana, near the tomb of the martyr saint. It was begun either at the end of Constantine's life or soon after his death. The mausoleum of his daughter, Constantina, now known as S Costanza, was built alongside the basilica's south flank. The best-preserved Constantinian building in Rome, S Costanza, is a double-shelled edifice consisting of a circular ambulatory encircling a tall cylindrical core capped by a dome. Although novel in Italy, its plan is strikingly reminiscent of the Anastasis Rotunda in the Holy Sepulchre compound (dedicated ca. 350), a comparison that may reflect an eastern Mediterranean influence on late Constantinian architecture in the Latin West. The fact that most of these ambulatory basilicas were paved with graves suggests that they served as funerary halls in which banquets commemorating the anniversaries of the departed were held. This type of church is also recorded at Andernos-les-Bains in south-west France. Source: Grove Art Online; http://www.groveart.com/ (accessed 2/3/2008)