Inside, the center of the floor descends three steps into the stone, indicating the location of the first dedicated worship building in Fellport. Known as the Mithraeum, it provided worship space for the Cult of Mithras, a monotheistic-leaning Ionian god with a complex system of indoctrination and a healthy appreciation of shared meals among its faithful. The first Mithraeum building burned down 311 years ago, to be replaced by the larger Second Mithraeum and then the Third Mithraeum when the second one fell in an earthquake 27 years after that. During this time, Mithras's influence began to wane in favor of the older pantheon of squabbling gods. 200 years ago, the current Divinity Sanctum structure opened for use, allowing the faithful from any religion to pay their respects. Some people still refer to the Divinity Sanctum as the Mithraeum, though the current structure dwarfs the first Mithraeum.
Entering the structure today, the lightness and openness of the space under the dome still makes people's jaws drop in wonder. Shrines to individual gods line the walls and stand in aisles of kiosks across the floor, like booths at a Convention of the Divine. The sunken Mithraeum space remains clear for worshippers, as it provides the best light and view of the dome, but the modern floor bustles with the rites and competing incense of a riot of competing clergy, arranged at random. Indeed, the layout of the shrines changes by lottery every three months, allowing the desirable spots near entrances to change hands to eliminate apparent favoritism. It resembles a nomad camp crammed full of every religion known. Nobody thought the lottery system would work, but Justicar Genna Sinclair convinces everyone to abide by its results year after year.
One kiosk near every entrance to the structure displays a white banner with a red triangle pointing skyward. These kiosks serve as healer stations, where anyone can appeal for treatment of injuries, diseases, poisons, curses, and other afflictions at any time, day or night. Usually this involves a donation of some sort to the deity on duty, and clerks record all healing requests for fairness. Many clerics have scrolls and potions for sale as well, but the availability changes every four hours when shifts change.
The assignment schedule for healer kiosks allow the various religions to choose times in reverse order of the shrine lottery, so the best-placed shrines have the least-lucrative healer time slots. An adjunct building just cliffside of the Divinity Sanctum serves as a hospital for longer-term treatment. It also has white banners with a red triangle pointing skyward.
Theological and philosophical debates happen hourly in the Divinity Sanctum. Some residents take their meals in the Mithraeum just to watch the verbal fireworks fly. Most of the clergy have dedicated space elsewhere for rites and festivals, but almost everyone maintains a presence in the Sanctum.
The Divinity Circle maintains the building and grounds, and they resolve disputes between members as impartially as possible. Any religion can join the Circle and ask for space to place a shrine, and they will enter the next lottery. Members pay quarterly dues to the Circle along with a percentage of any transaction within the Sanctum, and they provide manpower for healer stations in the Sanctum and the hospital next door.
The Divinity Sanctum turns 200 years old at the end of the year, so the Circle has started to plan a festival to mark the occasion.
Note: I based the Divinity Sanctum building itself on the Hagia Sophia from our world. Byzantine architecture as an evolution of Roman architecture seems a good basis to mirror the more cosmopolitan influence of the wider world of Beneterra on Ionian architecture. And I love the idea of a dome, even if it screws up the view of the harbor from the next higher level of Fellport.