Kulb sits in Batn-El-Hajar - "the belly of stones" - a craggy, barren stretch of granite and rock between the second and third cataracts of the Nile. The usual ribbon of alluvial farmland that hugs the Nile elsewhere is missing here. Instead the river runs between walls of black rock, with only small patches of arable land wherever the gorge briefly widens. The village has two districts, Kulb West and East Kulb, on opposite banks of the river, with the one-kilometer island of Kulubnarti between them. It is about 130 km south of Wadi Halfa, just north of the Dal Cataract. The country is harsh. The Romans understood that these granite mountains divided the Egyptianized Upper Nubia culturally from everything south of them. Even today the road south from Wadi Halfa winds through this landscape for hours before the terrain softens.

By the late sixth century, Nubia had converted to Christianity. For nine hundred years the faith dominated the region. Then, in the fourteenth century, Islam gained control of territory south of the Third Cataract, and Christianity began to retreat. In the stony isolation of Batn-El-Hajar, Christians held on longer. Kulubnarti has been inhabited since about 1100 AD, and was used as a Christian refuge into the fifteenth century - one of the last known places in Nubia where Christian worship continued after the surrounding region had largely converted to Islam. A fortress on the island may have existed even before the Christian era. The domed Kulubnarti church, site 21-S-1 in archaeological notation, is remarkable precisely because of what it isn't: it is not a basilica with a long nave, as most Nubian churches were. It is a centrally planned building, a square or near-square with a dome above, and it is the only surviving example of such a plan in Lower Nubia.

The first sketches of the domed church were made at the beginning of the twentieth century by the English Egyptologist Somers Clarke, who published them in 1912 in Christian Antiquities in the Nile Valley. In March 1964, Friedrich Wilhelm Deichmann, Erich Dinkler, Peter Grossman, and other members of the German Archaeological Institute Cairo surveyed the island. Following the Aswan High Dam construction, urgent salvage archaeology ensued. The domed church was excavated in early 1968 under James Knudstad. Dinkler and Grossman dug in the southern Batn-El-Hajar in 1967, returning in 1968 and 1969 for campaigns at Kulb and on the nearby islands of Sunnarti and Turmuki. They traced the perimeter wall of the Kulb fort. William Adams Yewdale led University of Kentucky teams in 1969 and 1979, extensive excavations that covered the island and the adjacent mainland. The finds document a continuous human presence from the A-Group culture of the early third millennium BC all the way to the Islamic period.

There is a pattern in Nubia: the most unreachable places preserve the most. Kulb survived continuous raids and conquests because it was buried in bad country - hard to reach, not worth conquering, too stony for the usual Nile prosperity but stubborn enough to keep a population alive. Its church survived because the stone walls did not invite demolition. The rock inscriptions of the Old Kingdom mining officials survived because no later generation had reason to deface them. Lake Nasser rose but did not reach this far south; the Aswan High Dam's reservoir stops short of Batn-El-Hajar. From the air, Kulb reads as a dark line of black rock with a strip of green on either side of the Nile, narrow enough that the river dominates the scene. The island of Kulubnarti sits mid-stream, long and low, with the village at both ends and the ruins between. A very old place, kept by the very hardness of the country around it.