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Wildfire perimeter

Backbone

Burned 40,858 acres (165 km², 63.8 mi²) in AZ during 2021.

IRWIN {115E090B-6F4F-4… USFS AZ fire history 2021 fires
Acres burned
40,858
165 km²
Year
2021
FIRE_YEAR field
State
AZ
POOState region
Reporting agency
USFS
NIFC source
01 Perimeter shape

The fire's footprint

Simplified polygon (≤0.001° tolerance). 4 rings. Centroid 34.407°, -111.610°.

NW: 34.497°N, 111.782°W SE: 34.317°N, 111.438°W

About this perimeter

Sourced from the NIFC InterAgency Fire Perimeter History ArcGIS service. Polygon geometry has been simplified to ≤0.001° tolerance for storage; original full-fidelity perimeters are at fire.nifc.gov. We track all 75,044 documented historical perimeters; this detail view renders the top 1,000 by acreage. The shape above is rendered fully server-side with no JavaScript or external mapping library — it preserves the polygon's shape but not its precise geographic placement on a basemap.