We build on open and public-domain data. Thank you to the agencies, projects and volunteers who make it available.
Sources
| Source | License | Used for |
|---|---|---|
| GeoNames US gazetteer | CC BY 4.0 | Populated places, time zones, elevations, counties, natural features |
| USGS Geographic Names Information System (GNIS) | Public domain (U.S. Government) | Official names and coordinates of waterfalls, peaks, lakes, passes and springs (via GeoNames) |
| U.S. Census Bureau Gazetteer Files | Public domain (U.S. Government) | County centroids and land area for county hubs |
| Wikidata | CC0 | Landmarks, protected areas, lighthouses, covered bridges, ghost towns, dark-sky places, popularity signals |
| DarkSky International: International Dark Sky Places (via Wikidata) | Facts (designations) | Certified dark sky parks, sanctuaries, reserves and communities |
| FHWA National Scenic Byways & All-American Roads (via Wikidata) | Public domain / CC0 | Scenic byway list |
| OpenStreetMap (Overpass API) | ODbL 1.0 — © OpenStreetMap contributors | Named viewpoints, waterfalls, lighthouses, hot springs, arches, covered bridges, observation towers |
| National Park Service Data API | Public domain (U.S. Government works); third-party photos keep their own rights | Park units, descriptions, weather & directions, named overlooks and places |
| NPS commercial filming & still photography permits | Public domain | Photography permit rules (54 U.S.C. 100905) |
| Recreation Information Database (Recreation.gov RIDB) | Public domain (U.S. Government) | Campgrounds near photo locations, federal recreation areas |
| NASA POWER climatology (MERRA-2) | Public domain (NASA) | Monthly cloud cover, temperature, precipitation and wind for every location |
| iNaturalist API | Observation data CC BY-NC; photos under the license shown with each photo | Bloom calendars, bird / butterfly / mammal seasonality by state and month, species photos |
| Lensfun lens & camera database | CC BY-SA 3.0 | Camera mounts and crop factors, lens focal ranges and apertures, mount compatibility |
| U.S. Naval Observatory Astronomical Applications API | Public domain (U.S. Government) | Full moon and new moon dates |
| NOAA Tides & Currents (CO-OPS) | Public domain (NOAA) | Nearest tide station and live tide predictions for coastal spots |
| NOAA Space Weather Prediction Center | Public domain (NOAA) | Live Kp-index forecast on aurora pages |
| National Weather Service API | Public domain (NOAA/NWS) | Live sky-cover forecast widget on location pages |
| Wikimedia Commons | Each image under its own free license (CC BY, CC BY-SA, CC0, public domain), credited on the page | Location photos with attribution |
| Wikipedia (English) | CC BY-SA 4.0 — excerpts are credited and linked on each page | Short background excerpts for landmarks |
| City & state flags (Wikidata P41 / Wikimedia Commons) | Mostly public domain; each flag credited with its Commons license | Flags shown on city and state pages |
| Sun & moon algorithms (after NOAA / Meeus, as in SunCalc) | Computed by us | Sunrise, sunset, golden & blue hour, moon phase and moonrise |
| Walker's law sky-glow model | Computed by us from GeoNames populations | Estimated Bortle class and zenith brightness |
| IGRF geomagnetic dipole | Computed | Geomagnetic latitude and Kp thresholds for aurora |
| International Meteor Organization working list | Facts | Meteor shower activity periods, ZHR and radiants |
| ExifTool tag documentation | Facts | Shutter count tag names by camera maker |
| FAA / NPS / USFWS / USFS regulations | Public domain | Permit and drone notes |
Attribution notes
- Map data © OpenStreetMap contributors, available under the Open Database License (ODbL).
- Wikipedia excerpts are licensed CC BY-SA 4.0 and linked to their articles.
- Photos from Wikimedia Commons and iNaturalist are credited on each page with their individual licenses.
- Lensfun data is CC BY-SA 3.0.
- GeoNames data is CC BY 4.0.