Ancient rivers carved the tops and exposed edges of these blocks, removing some layers and sculpting intricate formations in others. The Paria Valley was created and later widened between the plateaus. The Paria River and its many tributaries continue to carve the plateau edges. Rushing water carrying dirt and gravel gully the edges and steep slopes of the Paunsaugunt Plateau on which Bryce Canyon National Park lies. With time, tall thin ridges called fins emerge.
Fins further erode into pinnacles and spires called hoodoos.
These in turn weaken and fall, adding their bright colors to the hill below.