San Gabriel National Mountains Monument

San Gabriel Mountains National Monument

San Gabriel Mountains National Monument Expanded by President Biden

On May 2, 2024, President Biden expanded the San Gabriel Mountains National Monument. This designation enlarges the monument by 105,919 acres, and together with the 2014 designation by President Obama, the San Gabriel Mountains National Monument now stretches more than 452,000 acres. The monument protects rich cultural history, striking geologic features, and vibrant ecological diversity.

More information: San Gabriel Mountains National Monument


Maps

Map showing 2024 and 2014 boundaries

Boundary map (low-resolution)

Boundary map (high-resolution)


Background

On Oct. 10, 2014, President Barack Obama designated 346,177 acres on the Angeles National Forest as the San Gabriel Mountains National Monument.

Soaring high above the Los Angeles Basin, the San Gabriel Mountains are within 90 minutes of 15 million people in the Los Angeles Basin. These are working lands that provide Angelenos 70 percent of their available open space and 30 percent of their drinking water.

The designation will help ensure these lands remain a benefit for all Americans through tribal antiquities that provide a glimpse into Indigenous cultures who call this area their homelands, an observatory that brings the world the cosmos, habitat for rare and unique plants and animals, and outdoor recreation opportunities for millions of visitors each year.