Mojave Trails National Monument, Nature reserve in California, US.

Mojave Trails National Monument is a 1.6-million-acre national monument in San Bernardino County, southeastern California, between Interstates 15 and 40. It borders the Mojave National Preserve to the north and Joshua Tree National Park to the south, and is administered by the Bureau of Land Management. Its terrain mixes desert mountain ranges, ancient lava flows, and sand dunes such as the orange-pink Cadiz Dunes.

President Barack Obama designated Mojave Trails National Monument on February 12, 2016, together with Castle Mountains and Sand to Snow, under Bureau of Land Management administration. The designation covered about 1.6 million acres, of which 350,000 acres were already wilderness. People have lived in the area for more than 10,000 years; in 1829 the Mexican explorer Antonio Armijo laid out the Old Spanish Trail through it, and from 1942 to 1944 over a million soldiers trained at camps such as Ibis and Iron Mountain.

The monument contains preserved sections of Route 66 and ancient Native American trading routes that are still visible in the landscape. These paths show how people have moved through and used this land over many generations.

Visitors should bring a high-clearance vehicle since many roads are rough and require four-wheel drive for access. Water is essential to carry in abundance, as reliable water sources are scarce throughout the monument.

The Trilobite Wilderness Area within the monument is named for trilobites, but the monument's documented paleontological sites are not described in the sources as containing fossils of these animals. The name refers to a designated wilderness area rather than a fossil bed visitors can inspect.