The second king of the 12th Dynasty was the son of Amenemhet I and Queen Nefrutoten. Senwosret served as co-ruler with his father for more than ten years. He received news of his fathers death while away on a campaign. During his reign he extended Egypts borders to the area between the Second and Third Cataract. He established the fortress of Kerma. Senwosret mined gold, copper and granite. After securing Egypts borders he erected buildings along the Nile and refurbished existing temples. He built a funerary complex at Lisht. His pyramid consisted of separate compartments filled with sand and then covered with limestone. A second layer of stone completed the structure. His son, Amenemhet II, served with him as co-ruler and assumed the throne when Senwosret died in the 45th year of his reign.