216 
NATURAL BRIDGES OF UTAH 
plateaus. The accompanying sketch (Fig. 16) gives a generalized 
north>south cross-section showing the principal geological con¬ 
ditions; also the manner in which the topographic divide mi¬ 
grates as the cliffs recede. 
Southward-trending streams flow against the dip of the beds 
and as they approach each cliff they necessarily incise themselves 
deeper and deeper into the formations. Then, as they pass beyond 
the cliff, they travel in the open for a short distance and again 
bury themselves in canyons of gradually increasing depth. Thus 
it will be seen that contemporaneous with the recession of the 
cliffs, the streams embed themselves into successively lower forma¬ 
tions, and by so doing retain many of the characteristics which 
they formerly possessed. Probably some of the most spectacularly 
entrenched meanders in the world are present in this southern 
Utah region. 
The Mormon town of Blanding is the outfitting point for 
the last forty miles of the trip to the San Juan bridges. It is 
situated at an elevation 7000 feet above tide, and immediately 
at the base of Blue Mountains. From this point the trip is made 
on horseback. In traveling westward from Blanding to the 
bridges, one passes over a great platform having a geological 
structure quite similar to that shown in figure 16, similar in the 
sense that one travels alternately against the dip of the formations 
and down steep escarpments, but dissimilar in that the two distal 
places — the outfitting point and the bridges — are practically at 
the same elevation. At Blanding one starts on rocks of Cretacic 
age, and at the bridges one has stratigraphically descended to the 
Triassic level, and yet has maintained an equal topographic posi¬ 
tion. This, of course, means that the beds dip toward the east 
at rather low angles. 
The highest point between Blanding and the bridges is reached 
about midway between the two places, specifically where the 
trail passes over a broad uniclinal structure locally known as 
Elk Mountain. The eastern face of this upland constitutes a 
long gradual slope, while the one on the west is sharp and abrupt. 
Kigalia, a ranger station, situated near the crest of this mountain 
and right in the midst of a primitive forest, affords a wonderful 
camping place for all who go that way. The greater part of the 
country between Blanding and the bridges is arid, maintaining 
