The long history of Egyptian military activity in Lower Nubia may indicate that Kerma was perceived as a threat to Pharaonic Egypt at varying times. Principal Egyptian fortifications were built in the middle Nile Valley during the Middle Kingdom.[10] These were to secure the Upper Egyptian border against raids from Kerma, and more than likely and to protect the valuable trade routes between the two regions.[2] Both during the Middle and New Kingdoms, the resources Kerma possessed – gold, cattle, milk products, ebony, incense, ivory, etc. – were much coveted by Egypt. Its army were built around archers.[11]