The Cajon Ruins site is a few miles south of the main park site. It is inside 40 acre fenced area just inside the boundary of the Navajo Indian Reservation deep in the southeast corner of Utah. The trail is very short, leading to a small group of pueblo ruins perched on the edge of the small Cajon canyon.
The terrain is dry and nearly treeless sagebrush country. There is a seep of water at the bottom of the canyon that made this site livable. To the southwest the spires of Monument Valley are vaguely visible.
The Hovenweep sites are known for their diversity of masonry designs, using squares, rectangles, ovals and D shapes. The people that lived here grew corn, beans, and squash. They are thought to have abandoned the area in the late 1200s and moved further south.
There isn't much of a hike here, more of a stroll to observe the ruins. Within the 40 acre fenced area there is room to wander around and view the surrounding mountains. There aren't any trees here to obscure the views.