We offered to pay Mogrovejo a gratificación of a sol, or Peruvian silver dollar, for every ruin to which he would take us, and double that amount if the locality should prove to contain particularly interesting ruins. This aroused all his business instincts. He summoned his alcaldes and other well-informed Indians to appear and be interviewed. They told us there were "many ruins" hereabouts! Being a practical man himself, Mogrovejo had never taken any interest in ruins. Now he saw the chance not only to make money out of the ancient sites, but also to gain official favor by carrying out with unexampled vigor the orders of his superior, the sub-prefect of Quillabamba. So he exerted himself to the utmost in our behalf. The next day we were guided up a ravine to the top of the ridge back of Lucma. This ridge divides the upper from the lower Vilcabamba. On all sides the hills rose several thousand feet above us. In places they were covered with forest growth, chiefly above the cloud line, where daily moisture encourages vegetation. In some of the forests on the more gentle slopes recent clearings gave evidence of enterprise on the part of the present inhabitants of the valley. After an hour's climb we reached what were unquestionably the ruins of Inca structures, on an artificial terrace which commands a magnificent view far down toward Paltaybamba and the bridge of Chuquichaca, as well as in the opposite direction. The contemporaries of Captain Garcia speak of a number of forts or pucarás which had to be stormed and captured before Tupac Amaru could be taken prisoner. This was probably one of those "fortresses." Its strategic position and the ease with which it could be defended point to such an interpretation. Nevertheless this ruin did not fit the "fortress of Pitcos," nor the "House of the Sun" near the "white rock over the spring." It is called Incahuaracana, "the place where the Inca shoots with a sling." Incahuaracana consists of two typical Inca edifices--one of two rooms, about 70 by 20 feet, and the other, very long and narrow, 150 by 11 feet. The walls, of unhewn stone laid in clay, were not particularly well built and resemble in many respects the ruins at Choqquequirau. The rooms of the principal house are without windows, although each has three front doors and is lined with niches, four or five on a side. The long, narrow building was divided into three rooms, and had several front doors. A force of two hundred Indian soldiers could have slept in these houses without unusual crowding.