During the 12th Dynasty, a succession of strong rulers devoted much of their energy to developing the natural resources and improving the infrastructure of the kingdom. Amenenhat I established a new royal city, Itjtawy, near Faiyum, and secured the eastern Nile delta, a perennial weak point in Egypt’s defences, with a string of forts and regular patrols. This was to safeguard the region against invasion and to protect the key trade routes of the Ways of Horus. Senusret I added a string of fortresses between the first and second cataracts to protect his territorial gains from Nubia, a programme that was augmented by Senusret III. Amenenhat II and III built the Bahr Yusuf canal linking Lake Moeris to the Nile and, by building a barrage, protective embankments and waterwheels, generated a system of irrigation which greatly expanded the fertile land area round Faiyum.