NOAA S-57 chart cell
Approaches to San Francisco Bay - South of the Farallon Islands, CA
US4CA1AH
- Usage band
- Approach · code 4
- Current edition
- 1.0
- Features
- 33
- S-57 layers
- 18
- Published
- Jan 16, 2026
- Manifest updated
- Jun 22, 2026, 2:51 PM UTC
Coverage
- North
- 37.50000° N
- South
- 37.20000° N
- West
- 123.30000° W
- East
- 123.00000° W
- Center
- 37.35000° N, 123.15000° W
- Bounds area
- 258 sq nm
- Feature density
- 0.128 / sq nm
Chart Statistics
18 largest layers shown
- Average features per layer
- 1.8
- Smallest layer
- 1
- Largest layer
- 5
- Area sq km
- 885
- Features per sq km
- 0.0373
- SBDARE Seabed area 5
- SOUNDG Sounding 5
- M_QUAL Data quality 4
- SEAARE Sea area 3
- DMPGRD 2
- RESARE 2
- CBLSUB 1
- CONZNE 1
- COSARE 1
- CTNARE Caution area 1
- DEPARE Depth area 1
- EXEZNE 1
- M_COVR Coverage 1
- M_NPUB 1
- M_NSYS 1
- MAGVAR Magnetic variation 1
- RDOCAL 1
- TESARE 1
Nearby Chart Cells
Approach usage band
Current Edition Files
The NOAA ZIP archive is the upstream source for this chart cell; the other files are Open Ships generated derivatives for web and GIS use.
- Original NOAA ZIP archive https://www.charts.noaa.gov/ENCs/US4CA1AH.zip
- S-57 cell https://charts.openships.ai/noaa/s57/approach/US4CA1AH/1.0/US4CA1AH.000
- GeoJSON https://charts.openships.ai/noaa/s57/approach/US4CA1AH/1.0/US4CA1AH.geojson
- GeoParquet https://charts.openships.ai/noaa/s57/approach/US4CA1AH/1.0/US4CA1AH.parquet
- Metadata JSON https://charts.openships.ai/noaa/s57/approach/US4CA1AH/1.0/metadata.json
Editions
| Edition | Published | Metadata |
|---|---|---|
| 1.0 | Jan 16, 2026 | metadata.json |