Lake Powell is a storage facility for the Upper Basin states of the Colorado River Compact (Colorado, Utah, Wyoming, and New Mexico). The Compact specifies that the Upper Basin states are to provide a minimum annual flow of 8.23 million acre feet (10 km³) to the Lower Basin states (Arizona, Nevada, and California).

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Rainbow Bridge National Monument is administered by Glen Canyon National Recreation Area, southern Utah, USA. Rainbow Bridge is often described as the world’s largest natural bridge. The span of Rainbow Bridge is 275 feet (84 m), and at the top it is 42 feet (13 m) thick and 33 feet (10 m) wide. Two other natural arches, Kolob Arch and Landscape Arch, both also in southern Utah, have confirmed spans several meters longer than Rainbow Bridge, but by most definitions of the terms are described as arches but not bridges. With a height of 290 feet (88 m) Rainbow Bridge does indeed stand taller than either of its longer competitors, but it is outdone by Aloba Arch at 394 feet (120 m), which is in turn dwarfed by the world’s tallest arch, Tushuk Tash in China at an estimated 1,200 feet (366 m). It is probably the most accessible of the large arches of the world, as it can be reached by a two-hour yacht ride on Lake Powell or by hiking several hours overland from a trailhead (obtain a permit from the Navajo Nation in Window Rock, Arizona).

Called the Artist Drive Formation, the rock unit provides evidence for one of the Death Valley area’s most violently explosive volcanic periods. The Miocene-aged formation is made up of cemented gravel, playa deposits, and much volcanic debris, perhaps 5,000 feet (1500 m) thick. Chemical weathering and hydrothermal alteration are also responsible for the variety of colors displayed in the Artist Drive Formation and nearby exposures of the Furnace Creek Formation.

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