• Sunset at Lake Mead's Boulder Basin

    Lake Mead

    National Recreation Area AZ,NV

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  • I-15 REOPENED, LAKE MEAD ENTRANCE FEES TO RESUME SUNDAY

    The Nevada Department of Transportation reopened a northbound and southbound lane of Interstate 15 Sept. 12; therefore, Lake Mead National Recreation Area entrance fees will resume Sept. 14. More »

  • Important Notice to Mariners

    Lake Mead water elevations will be declining throughout the summer. Before launching, check lake levels, launch ramp conditions, changes to Aids to Navigation and weather conditions by clicking on More »

  • Areas of Park Impacted by Storm Damage

    Strong storms rolled through Lake Mead National Recreation Area Aug. 3-4, causing damage to some areas of the park. Crews are working to restore the below locations. Debris may be present in other areas of the park, as well, especially in the backcountry. More »

Fortification Hill

Fortification Hill

About 18 million years ago a tectonic upheaval began that profoundly marked the present Lake Mead NRA landscape.

Thirteen million years ago, the crust around the Lake Mead area was stretched and thinned so iron and magnesium-rich magma and basalt, poured out of the ground and covered the landscape. The darker lava produced many of the black volcanic flow-capped mesas, such as Fortification Hill and Callville Mesa, seen in many parts of Lake Mead National Recreation Area.

Mineral-rich fluids trapped in older rock were mobilized when hot magma was injected into them. These hot, hydrothermal fluids percolated up through some of the igneous rock formations, including the Paint Pots pluton at the base of Fortification Hill, imparting their beautiful coloration!

Area Map


Fortification-Hill-Small-Combined-Map

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Did You Know?

Geometric Petroglyphs on rocks

As early as 3,000 years ago, people inhabiting the Southwest began chiseling and painting pictures on rocks and cliff walls. Preserved by the dry climate, much of this rock art ranging from complicated geometric designs to huge figures, remains to puzzle, astonish, and awe modern-day viewers.