See the context of this sign.

Balanced Rock

Thousands of years ago a huge boulder of
conglomerate broke from the cliff above and
rolled to a stop here. Since then, at least 6 feet
(2.8m) of this slope has eroded away.

Uiltimately, the softer rock now protected by
the umbrella of harder conglomerate will erode
and the boulder will topple again to the ground.
Eventually, weathering will also break down the
boulder. Look for nearby piles of gravel that
mark the sites of former balanced rocks.

Similar erosion is occurring along all the cliffs in
this area. The softer rock is washing away, leaving
overhangs of hard rock which will someday break
off and roll down the slope. This process is known
as "cliff retreat."

Don't miss the rest of our virtual tour of Glen Canyon National Recreation Area in 355 images.