How each site is found, sourced and rated
The Atlas maps the public record of nuclear weapons infrastructure: design laboratories, fissile material plants, warhead production and storage, test sites, delivery-system bases, command sites, uranium mining and dual-use plants with a weapons connection. It updates the static site lists that research groups published in the 1990s and 2000s.
Every site cites the pages it came from
Every site carries at least one citation to a page opened during research, a status date taken from that source, and the date an editor last checked it. Status describes what the sources reported on that date, not a live condition. Where sources disagree, its status is Disputed.
Three confidence levels
- High: declared by the operating government or IAEA, or consistently documented by the main reference institutes.
- Medium: reported by one established institute or reference work, or with uncertain detail.
- Low: single-source, inferred, or contested role.
Points are accurate to about a kilometer, never to a building
Points are rounded to two decimal places, about one kilometer. Points with area precision mark the town, field or region rather than the facility, accurate to roughly ten kilometers. Silo fields and garrisons appear as one point. The Atlas does not mark individual buildings, silos or launch positions, and it gives no technical or security detail beyond a site's role and history.
Coverage
Russian national-level warhead storage sites are included where public sources name them; several remain unconfirmed.
How NPEC’s Interactive Nuclear Atlas was merged in
Many sites come from the Nonproliferation Policy Education Center's Interactive Nuclear Atlas. Each NPEC pin was checked against the existing records: pins that match a site add NPEC as a further source, near-duplicate pins are combined, and the rest become new records cited to the NPEC map they came from. Pins with clear location or attribution errors were corrected or left out, and the reason is recorded in the project's review file. NPEC rarely states a site's current status, so these records show the status Not Stated, use area precision, and are rated medium confidence, or low where NPEC's own wording is hedged or other sources disagree. Descriptions quoted from NPEC are shortened and credited.
Where the borders, relief and marker layout come from
Country borders and coastlines come from Natural Earth at 1:10m scale. Land borders are drawn as vector lines, so they stay sharp at every zoom. Relief shading is Natural Earth's Shaded Relief Basic (public domain, derived from SRTM Plus elevation data), embedded at 10,800 by 5,400 pixels; the highland tint comes from the elevation image distributed with the open-source three-globe library (MIT license). Where several sites would overlap on screen when zoomed in, their markers fan out around the shared spot, with a thin line to each true position. Coastal sites can still appear just offshore where the coastline is simplified.
Search finds sites by name and by nearby place
Search covers each site's name, other names, functions, country and operator, plus nearby place names: up to three towns within 30 kilometers, the state or province and the county or district, and up to two postal codes whose centers lie within 20 kilometers. It does not search site descriptions. Place names come from GeoNames' list of populated places, and postal codes from the GeoNames postal-code export (both CC BY 4.0, geonames.org). GeoNames has no postal codes for Israel, Iran or North Korea and only partial coverage of China. Because site points are rounded and most mark an area, "nearby" means near the published point; these terms help you find a site and are not a statement of its address.
What the live map leaves out
The map shows sites with a current or plausible nuclear weapons role. Closed and historic sites, civil fuel-cycle plants with no recorded weapons role, units and bases with no assessed nuclear role (such as BrahMos missile units), and Iran's missile bases have been moved to an archive. The archive is published with the dataset and can be restored.
How program tours choose sites and draw lines
A program tour follows one warhead family through a country's nuclear weapons complex, from its uranium to its dismantlement; the U.S. tour follows the W87. Each stage stops at a single current site: the one the sources name for that job, or, where they do not, the site the atlas assesses as most likely. A line traces the warhead's story from each stage to the next and stays on the globe as the tour goes on. A solid line leads to a site whose role for that warhead is documented; a dotted line leads to an assessed site. The lines are not routes or shipments, and tours give no routes, schedules, quantities or security details. Every stage cites its sources.
Version and last check
Send a correction with a citation
Corrections are accepted with a citation. The dataset is published as JSON, CSV and GeoJSON with a changelog.