Researchers estimate the church measured 47 meters wide and around 57 meters long – making it bigger than the White House in Washington DC A team of Polish and Sudanese archaeologists has uncovered a monumental staircase and the original floor of one of medieval Africa's most important churches that may have shaped religious architecture across the region. The discoveries were made at Old Dongola city in northern Sudan, once the capital of the Nubian Christian Kingdom of Makuria and one of northeastern Africa's most significant archaeological sites. Researchers from the University of Warsaw's Polish Center of Mediterranean Archaeology (PCMA), led by Professor Artur Obłuski, first identified the structure, known as the Great Church of Jesus, in 2021. During their latest excavations, the team exposed an imposing staircase leading into the church and buttresses supporting its apse. They also reached the building's original floor level for the first time. An architectural trendsetter Obłuski believes the church may have been an architectural trendsetter for medieval Nubia, comparing its potential influence to that of the Hagia Sophia in Constantinople, now Istanbul. So far, only a small section of the Great Church of Jesus has been excavated. Researchers estimate it measured 47 meters wide and around 57 meters long, with a possible height of 21 meters. "It is a building larger than the White House in Washington. And we plan to excavate it," Obłuski said, adding that the work would require exceptionally deep trenches and substantial resources. Another church The Polish-Sudanese team also made an unexpected discovery: another church on the upper floor of a structure adjoining the monumental building. Although its walls survive to a height of just one meter, archaeologists recovered numerous fragments of painted plaster, filling six large storage racks. Further finds included fragments of Greek inscriptions containing biblical hymns, including part of the prayer of Hannah, the mother of the prophet Samuel. Decades of Polish research Polish archeologists have been involved in research efforts in Old Dongola since the 1960s. Earlier this year, they uncovered a 400-year-old text confirming the existence of an African king who was previously thought to have been a legend. Alongside the recent archaeological work, the expedition installed a solar-powered system funded by Poland's foreign ministry. The system will supply electricity to pumps drawing water from the River Nile for around 10,000 local residents and nearby farmland.