such as the Eastern and Western Deffufas (50 by 25 by 18 meters). They also had rich tombs with possessions for the afterlife and large human sacrifices. George Andrew Reisner excavated sites at the royal city of Kerma and found distinctive Nubian architecture, such as large pebble covered tombs (90 meters in diameter), a large circular dwelling, and a palace-like structure. Classic Kerma rulers employed "a good many Egyptians", according to the Egyptian Execration texts. Kerma culture was militaristic, as attested by many archers' burials and bronze daggers/swords found in their graves. Other signs of Nubia's military prowess are the frequent use of Nubians in Egypt's military and Egypt's need to construct numerous fortresses to defend their southern border from the Nubians. Despite assimilation, the Nubian elite remained rebellious during Egyptian occupation. There were numerous rebellions and "military conflict occurred almost under every reign until the 20th dynasty". At one point, Kerma came very close to conquering Egypt: Egypt suffered a serious defeat at the hands of the Kingdom of Kush. According to Davies, head of the joint British Museum and Egyptian archaeological team, the attack was so devastating that, if the Kerma forces had chosen to stay and occupy Egypt, they might have permanently eliminated the Egyptians and brought the nation to extinction. During Egypt's Second Intermediate period, the Kushites reached the height of their Bronze Age power and completely controlled southern trade with Egypt. They maintained diplomatic ties with the Thebans and Hyksos until the New Kingdom pharaohs brought all of Nubia under Egyptian rule from 1500 to 1070 BC. After 1070 BC, there were continued hostilities with Egypt, which led Nubians to concentrate in Upper Nubia. Within 200 years, a fully formed Kushite state, based at Napata, began to exert its influence on Upper (Southern) Egypt. Lower Nubia When the Middle Kingdom Egyptians pulled out of the Napata region around 1700 BC, they left a lasting legacy that was merged with indigenous C-group customs. Egyptians remaining at the garrison towns started to merge with the C-group Nubians in Lower Nubia. The C-group quickly adopted Egyptian customs and culture, as attested by their graves, and lived together with the remaining Egyptians in garrison towns. After Upper Nubia annexed Lower Nubia around 1700 BC, the Kingdom of Kush began to control the area. At this point, C-group Nubians and Egyptians began to proclaim their allegiance to the Kushite King