This view features a portion of the Virgin River as it flows along the canyon floor in Zion National Park.

Kodachrome Reproduction by Mike Roberts
The description states:
VIRGIN RIVER
ZION NATIONAL PARK, UTAH
Carved by the North Fork of the Virgin River, which the early Indians called Mukuntuweap, Zion Canyon is an ears of vertical gorges, towering colorful walls and cliffs.
–The Virgin River is a tributary of the Colorado, which is also known for carving the world-famous Grand Canyon in Arizona. This postcard likely dates from the 1950s.