The passageway seems to pull away as we approach, growing larger and larger in front of our eyes. 
That canyon is larger than past experience would let us imagine.  Finally, we paddle inside and we are in the nave of a cathedral, greater by many times than any made by man.  It's high water season, so our boats easily drift inside.  (Note the yellow raft about to land.)
Out of our boats, we are walking on a flat, smooth sand floor with arching walls closing overhead.  Sweeping turns plunge into giant, dark stream alcoves.  The occasional flash floods have, over the millenia, carved deeply because water and debris must make sharp turns in a serpentine route.  The Navajo sandstone is structurally firm, but slightly water soluble, the perfect combination for formation of these wondrous canyons.  Thoughts of flash floods remind us to keep aware of the weather in this land of sudden storms. Chris Suczek...of the above yellow raft 
This is one of Cathedral Canyon's many great stream alcoves.  We are standing in a cavernous grotto.  The ceiling above us reaches hundreds of feet over the opposite wall. We see downstream to the left and upstream to the right.
 
 
Click on the upstream part to 
see what lies further upstream.
One link in picture
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