BLM · Washington

San Juan Islands National Monument

San Juan Islands National Monument is a U.S. National Monument located in the Salish Sea in the state of Washington. The monument protects archaeological sites of the Coast Salish peoples, lighthouses and relics of early European American settlers in the Pacific Northwest, and biodiversity of the island life in the region. The monument was created from existing federal land by President Barack Obama on March 25, 2013 under the Antiquities Act.

From Wikipedia, licensed CC BY-SA 4.0.

National Monument431,571 acresBLMWA
Search Bureau of Land Management ↗

Facts

Where each comes from ↓
DesignationNational Monument
Managed byBureau of Land Management
StateWashington
Size431,571 acres (computed from the boundary polygon)
National Conservation Lands idNLCS002387
Center point48.5885, -122.9158
Night skyAbout as dark as the ground gets (Black Marble reading 10)

Boundary map

1 outline

Boundary, simplified to about 0.005 degrees

The outline is the agency boundary simplified for display, so small parcels and inholdings may not show. The agency page has the authoritative map.

Weather by month

NOAA climate normals →
Weather by month near San Juan Islands National Monument40°50°60°70°January: 3.95 inches of precipitation, 1.8 inches of snowFebruary: 2.60 inches of precipitation, 0.4 inches of snowMarch: 2.63 inches of precipitation, 0.1 inches of snowApril: 2.07 inches of precipitation, 0.0 inches of snowMay: 1.68 inches of precipitation, 0.0 inches of snowJune: 1.27 inches of precipitation, 0.0 inches of snowJuly: 0.71 inches of precipitation, 0.0 inches of snowAugust: 1.00 inches of precipitation, 0.0 inches of snowSeptember: 1.62 inches of precipitation, 0.0 inches of snowOctober: 3.24 inches of precipitation, 0.1 inches of snowNovember: 4.58 inches of precipitation, 0.6 inches of snowDecember: 3.83 inches of precipitation, 2.8 inches of snowJanFebMarAprMayJunJulAugSepOctNovDecJanuary: 41.0°F averageFebruary: 42.5°F averageMarch: 45.5°F averageApril: 49.7°F averageMay: 54.5°F averageJune: 58.1°F averageJuly: 61.7°F averageAugust: 61.7°F averageSeptember: 58.2°F averageOctober: 51.6°F averageNovember: 45.0°F averageDecember: 40.6°F average0 in1 in2 in3 in4 in5 inTemp °FInches
The line is the average temperature and the bars are average precipitation at Olga 2 SE, 5 miles from the center point at 80 feet, station USC00456096 in the NOAA monthly climate normals for 1991 to 2020. Precipitation totals about 29 inches a year. The dotted line is average snowfall, about 6 inches a year on the same inches scale.

Large units span more than one climate. The station stands in for the center point, and the outer parts of the boundary can be warmer or colder.

Limited data for this unit

This unit has no confirmed official page or nearby campgrounds in the sources this site reads. The boundary, size, agency and states above come from the agency layer.

Checked nightly. Sections appear when the sources fill in.

Explore

Nearby on the other atlases

National Park System units within 30 miles · Park Atlas
National Historical Park · Adjacent
San Juan Island National Historical Park
National Historical Reserve · 11 mi
Ebey's Landing National Historical Reserve
National Register listings within 15 miles · 66 in all · Register Atlas

Landmarks are listed first, then by distance from the boundary.

Reference

Questions people ask

How big is San Juan Islands National Monument?

431,571 acres, measured from the published boundary polygon. The agency’s own figure can differ where the boundary includes water or inholdings.

Source: How acreage is computed

Who manages San Juan Islands National Monument?

The Bureau of Land Management.

Source: Bureau of Land Management

What state is San Juan Islands National Monument in?

Washington.

Source: How states are assigned

How do I get to San Juan Islands National Monument?

A point inside the boundary is at 48.589, -122.916. San Juan Island National Historical Park is adjacent. The official page carries directions and the office address.

Source: Bureau of Land Management

How dark is the night sky at San Juan Islands National Monument?

NASA’s Black Marble night-lights image reads 10 on a 0 to 255 scale at the center point, about as dark as the ground gets.

Source: NASA Black Marble

Which national parks are near San Juan Islands National Monument?

San Juan Island National Historical Park (adjacent) and Ebey's Landing National Historical Reserve (11 mi). Park Atlas has fees, hours and alerts for each.

Source: Nearby on the other atlases

Are there historic places near San Juan Islands National Monument?

66 National Register listings within 15 miles, including W. T. Preston (snagboat) and Alderbrook Farmhouse.

Source: Register Atlas

Sources

  • Boundary, name: the BLM National Conservation Lands layer.
  • States: computed by intersecting the boundary with Census state polygons; a state is listed when it holds at least one percent of the area.
  • Acreage: geodesic area of the published polygon. The agency’s official acreage can differ where the boundary includes water, easements or inholdings.
  • Description: San Juan Islands National Monument on Wikipedia, CC BY-SA 4.0. The article was accepted because its title contains this unit’s name.
  • Campgrounds: the Campsite Atlas index of federal campgrounds, matched to this boundary at build time.
  • Night sky: NASA Black Marble (VIIRS, 2016 composite) sampled at zoom 6 around the center point.
  • Weather, alerts, air quality, river flow and earthquakes load live in your browser from NWS, AirNow, USGS and iNaturalist when you open the page.