Bureau of Land Management
BLM national monuments and conservation areas
56 national monuments, national conservation areas and similar designations managed by the Bureau of Land Management, 16 million acres together, from the BLM National Conservation Lands layer. Acreage is measured from the published boundary and can differ from the proclamation figure. Where the layer omits the designation from a name it is taken from the layer’s category code or, failing that, left as the name alone.
Data refreshed September 17, 2026.
The five largest
- 1Mojave Trails National MonumentBLM · CA1.8 million acres
- 2Steese National Conservation AreaBLM · AK1.2 million acres
- 3Grand Canyon–Parashant National MonumentBLM · AZ1.0 million acres
- 4Baaj Nwaavjo I'tah Kukveni – Ancestral Footprints of the Grand Canyon National MonumentBLM · AZ960,963 acres
- 5Black Rock Desert–High Rock Canyon Emigrant Trails National Conservation AreaBLM · NV815,434 acres
By state
Alaska1
- Steese National Conservation Area1.2 million acres
Arizona9
- Agua Fria72,510 acres
- Baaj Nwaavjo I'tah Kukveni – Ancestral Footprints of the Grand Canyon National Monument960,963 acres
- Gila Box Riparian National Conservation Area23,668 acres
- Grand Canyon–Parashant National Monument1.0 million acres
- Ironwood Forest National Monument189,931 acres
- Las Cienegas50,557 acres
- San Pedro Riparian National Conservation Area61,493 acres
- Sonoran Desert495,942 acres
- Vermilion Cliffs293,904 acres
California13
- Alabama Hills National Scenic Area18,831 acres
- Berryessa Snow Mountain National Monument421,086 acres
- California Coastal National Monument8,664 acres
- Carrizo Plain National Monument246,845 acres
- Cascade–Siskiyou National Monument170,596 acres · also OR
- Chuckwalla National Monument739,119 acres
- Fort Ord National Monument14,666 acres
- Headwaters Forest Reserve7,511 acres
- King Range National Conservation Area62,057 acres
- Mojave Trails National Monument1.8 million acres
- Piedras Blancas Outstanding Natural Area30 acres
- Sand to Snow National Monument174,844 acres
- Santa Rosa-San Jacinto Mountains National Monument279,535 acres
Colorado5
- Browns Canyon National Monument21,709 acres
- Canyons of the Ancients National Monument182,568 acres
- Dominguez–Escalante National Conservation Area218,593 acres
- Gunnison Gorge National Conservation Area65,053 acres
- McInnis Canyons National Conservation Area124,157 acres · also UT
Montana2
- Pompeys Pillar National Monument58 acres
- Upper Missouri River Breaks National Monument507,066 acres
Nevada8
- Avi Kwa Ame National Monument509,447 acres
- Basin and Range National Monument708,590 acres
- Black Mountain Pistones3,362 acres
- Black Rock Desert–High Rock Canyon Emigrant Trails National Conservation Area815,434 acres
- Gold Butte National Monument297,117 acres
- Numunaa Nobe160,109 acres
- Red Rock Canyon National Conservation Area201,531 acres
- Sloan Canyon National Conservation Area48,072 acres
New Mexico6
- El Malpais National Conservation Area263,107 acres
- Fort Stanton–Snowy River Cave National Conservation Area27,872 acres
- Kasha-Katuwe Tent Rocks National Monument5,403 acres
- Organ Mountains–Desert Peaks National Monument573,986 acres
- Prehistoric Trackways National Monument5,299 acres
- Río Grande del Norte National Monument311,107 acres
Oregon3
- Cascade–Siskiyou National Monument170,596 acres · also CA
- Steens Mountain Cooperative Management and Protection Area496,271 acres
- Yaquina Head Outstanding Natural Area91 acres
Utah7
- Bears Ears National Monument120,760 acres
- Beaver Dam Wash National Monument20,429 acres
- Grand Staircase–Escalante National Monument181,425 acres
- John Wesley Powell29,478 acres
- Jurassic819 acres
- McInnis Canyons National Conservation Area124,157 acres · also CO
- Red Cliffs National Monument61,170 acres
Washington1
- San Juan Islands National Monument431,571 acres