The story of this place
Around 310 AD the emperor Constantine built this vast brick audience hall as his throne room in Trier, then a capital of the empire. At 67 metres long and 33 metres high, its single unbroken interior is the largest surviving room from the Roman world, engineered with a hidden system of hot-air heating beneath the floor. Constantine sat enthroned in the apse, dwarfing petitioners in a calculated theatre of power. Over the centuries it was buried within a palace, then in the 19th century King Frederick William IV of Prussia had it restored as a Protestant church. Gutted by bombs in 1944, it was rebuilt as a spare, echoing hall — Roman engineering laid bare.