Square Tower House Ruin is situated in an eastern spur of Navajo Canyon, opposite a great bluff called Echo Cliff. An ancient approach to the ruin from the canyon rim is visible to the south of the dwelling. Footholes for ascent and descent had been cut in the cliff by the Indians which enabled them to reach the level on which the ruin is situated. The footpath now used by visitors parallels the ancient trail. Along the top of the talus this pathway splits into an upper and lower branch. The former, hugging the cliff, passes through the "Eye of the Needle"; the latter is lower down on the talus and is used by the stouter and older visitors. The Square Tower House cave is shallow, its back wall perpendicular, with roof slightly overhanging. At the extreme eastern end of the ruin the vertical cliff suddenly turns at right angles, forming an angle in which, high above the main ruin, there still remain walls of rooms. To these rooms, which are tucked away just under the canyon rim, with only their front walls visible, the name "Crow's Nest" is given. Logs, with their ends resting in notches cut in the rock actually support walls of masonry, as seen in the angle of this cliff. This is a well-known method of cliff-house construction. This ruin measures about 138 feet from its eastern to its western end. There are no streets or passageways as at Spruce Tree House and Cliff Palace. The rooms are continuous and compactly constructed, the walls being united from one end of the cave to the other, excepting for the spaces above the kivas. The absence of a cave recess to the rear of the ruin is significant as it allowed the cliff to be used as the back wall of rooms. Rooms in Square Tower House do not differ radically from those of Spruce Tree House and other cliff dwellings. They have smaller windows, door openings, and supports of balconies. The rectangular rooms were constructed above the ground; the circular rooms were subterranean. The former were devoted to secular and the latter to ceremonial purposes. THE TOWER The tower is, of course, the most conspicuous as well as the most interesting architectural feature of the ruin, being visible for a long distance as one approaches Square Tower House. Its foundation rests on a large boulder situated in the eastern section of the cave floor. This tower has three walls constructed of masonry, the fourth being the perpendicular rear wall of the cave. The masonry of the tower stands about 35 feet above the foundation, but the foundation boulder on which it stands increases its height over 5 feet. On a projecting rock on the west side above the tower is the wall of a small, inaccessible room which may have been used as a lookout or as an eagle house.