Rotunda – Thessaloniki

The Rotunda, a symbol of Thessaloniki, was built at the beginning of the 4th century AD, probably as a temple or mausoleum for Constantine the Great (306-337). The building is round with a dome approximately 30 m high and 25 m in diameter. Its walls are more than 6 m thick and its architectural structure is similar to the Pantheon in Roma. Not long after its construction, in the early years of the Byzantine Empire (330-1453), the Rotunda was converted into a Christian church and a sanctuary was added on its eastern side. Between 1524 and 1591, the structure became Thessaloniki's cathedral and then, when the city fell to the Ottoman Turks, it was converted into a mosque until 1912, when it was dedicated to Saint George. The inside of the structure, especially the dome and various niches, was originally embellished with beautiful mosaics, and the fragments that survive are considered to be genuine masterpieces of early Christian art.

The Rotunda is a unique structure, enrolled in the UNESCO World Heritage List, so the lighting system and luminaires adopted have been carefully chosen to ensure this splendid monument is treated with respect and properly preserved. Naturally, the lighting system also enhances this cultural treasure by allowing visitors to see it properly and thereby meeting the requirements of the company’s Social Innovation Through Lighting mission. The project is divided into three areas. The first focuses on the niches in the perimeter wall and their splendid depictions of fruit and birds. In this case the lighting is grazing and homogeneous, obtained with lines of light created by Underscore luminaires positioned by the side of the vault imposts of the niches. The second area is the dome with its precious green and gold background mosaics depicting Greek and Roman architectural compositions. The third area is the shrine and the fresco of the Ascension in the apse which dates back to the end of the   iconoclast period (842 AD).

For the dome and apse, Woody spotlights with a 40° optic and Woody Compact spotlights with a 50° optic and an excellent colour yield were used. The light beams with their different ranges and power have been carefully integrated to obtain a uniform, homogeneous light over the decorated surface. So now, the beauty of both the frescos and the mosaics can be enjoyed to the full without harming them, as LED lamps reduce the damage caused by infrared and ultraviolet radiation.