After his victory over the Chancas, Pachacutec decided to reinforce his authority by deposing the curacas who had not come to his assistance.

When he was organizing his punitive expedition, the news came that Inca Urco, the son and regent of Viracocha, had arrived in Yucay with an army. Without delay, Pachacutec and Inca Roca, his brother, marched on Yucay to confront Urco. During the battle on the banks of the Urubamba river, a well-aimed stone from Inca Roca's sling caught Urco in the throat and knocked him into the river.
Urco, weapons in hand, was dragged by the current to the promontory by the name of Chupellusca, where his foes killed him. Numerous curacas -most of them close to Cusco- were absorbed by the budding empire in its first stage of expansion. The main ones were the Ayarmacas, that were now permanently subdued, and the Ollantay Tambos.

After his victory, Pachacutec had the citadel-palace of Pisac built on a high peak, showing that this ruler not only was a great empire builder, but also an architect. However, the conquest of his that is of greatest interest in our story is that of the area of Picchu, where the Inca ordered a palace built for his return, including all its dependencies. Over the centuries, this place would come to be known by its present name of Machu Picchu. Thanks to contributions from the new manuscripts of the archives found by Luis Miguel Glave and María Isabel Remy, as well as later research by John E. Rowe, we now know that the whole area of Picchu, together with that of Ollantay Tambo, formed the private property of the Inca.
Proceeding with his military successes, Pachacutec, accompanied by Inca Roca, took over Amaybamba in the valley of La Convencion, building the Huaman Marca palace for his own use.

The same document that gives us this information tells us that the following ruler, Tupac Yupanqui, brought a number of mitimaes from Chachapoyas to populate the valley on the condition that they would plant coca groves. Additionally, the manuscript mentions the presence of another palace called Yanayacu, on the heights of Amaybamba. "When I was visiting that place, the former caretaker of the property told me that there were local reports on the presence of ruins, but that they had not been found yet."
Having cemented his power and ensured his possessions near the capital, Pachacutec embarked on the conquest of more distant lands. He successively defeated the Soras and the Lucanas, bringing their curacas and warlords as prisoners and parading them to celebrate his victories. Other tribal chieftains, noting his increasing power, preferred to accept his "overtures" of reciprocity rather than risk their lives in armed struggle.
After a short rest, the Inca gathered his armies again and, this time, decided to march against the chief of Collao. Thus, he faced off against the redoubtable Chuchi Capac de Hatun Colla, whom he was able to defeat after much fighting. With this victory, the cusqueños became owners of the extensive territories of Chuchi Capac, that included the jungle enclaves that produced the prized coca leaves and the fertile coastal lands that produced corn, peppers and salted fish. These were the Incas' first contact with the coastal ethnic groups.