This image shows the canyon floor and approaches to the structure called the Great White Throne. It was named, not by Mormon explorers, but by a Methodist minister who travelled in this canyon. It’s name is derived from a passage in the book of Revelations from the Christian bible.
The description states:
GREAT WHITE THRONE
ZION NATIONAL PARK
Nearly twice as high as the talked building in the world, the sheer walls of spectacular Great White Throne in Zion National Park rise 2, 447 feet above the floor of the canyon.
–The comparison to the tallest building is obviously no longer valid, as the tallest building in the world at this writing is the Burj Khalifa, which is 2,722 feet. This image likely dates from the 1950s.