This geological feature's dome-like shape reminded early explorers and settlers of the dome of the United States Capitol in Washington D.C., and lent the park its name.

[3] Capitol Dome is composed of Navajo Sandstone, which is believed to have formed about 180 million years ago as a giant sand sea, the largest in Earth's history.

[4] In a hot, dry climate, wind blew over sand dunes, creating large, sweeping crossbeds which date to the Jurassic.

Long after the sedimentary rocks were deposited, the Colorado Plateau was uplifted relatively evenly, keeping the layers roughly horizontal, but Capitol Reef is an exception because of the Waterpocket Fold, a classic monocline, which formed between 50 and 70 million years ago during the Laramide Orogeny.

This desert climate receives less than 10 inches (250 millimeters) of annual rainfall, and snowfall is generally light during the winter.