Natural Bridges - the Cedar Mesa Sandstone

The rock formation called the Cedar Mesa Sandstone actually has different lithologies ranging from uniform massive sandstone to thinly bedded fine-grained sandstone, siltstone, and locally red sandy shale. Some layers are more tightly cemented than others by mineral cements between the sand grains. These different rock characteristics give rise to the uneven canyon walls (having ledges, coves, overhangs, and massive walls). Ancestral Puebloans took advantage of these natural overhangs and alcoves to build dwellings, such as the ruins of this one located along the Sipapu Bridge Trail. Many ancient ruins of rock dwellings can be seen in the canyons throughout the park and surrounding region. Visitors must note that all prehistoric ruins and archeological artifacts are protected and should be left undisturbed.