NOAA S-57 chart cell
Mobile Bay Approach
US4AL1BB
- Usage band
- Approach · code 4
- Current edition
- 12.0
- Features
- 2,843
- S-57 layers
- 62
- Published
- Jun 9, 2026
- Manifest updated
- Jun 22, 2026, 2:51 PM UTC
Coverage
- North
- 30.30000° N
- South
- 30.00000° N
- West
- 88.20000° W
- East
- 87.90000° W
- Center
- 30.15000° N, 88.05000° W
- Bounds area
- 281 sq nm
- Feature density
- 10.1338 / sq nm
Chart Statistics
20 largest layers shown
- Average features per layer
- 45.9
- Smallest layer
- 1
- Largest layer
- 799
- Area sq km
- 962
- Features per sq km
- 2.95455
- SLCONS Shoreline construction 799
- OBSTRN Obstruction 216
- DEPCNT Depth contour 215
- DEPARE Depth area 196
- COALNE Coastline 154
- SBDARE Seabed area 116
- LIGHTS Light 114
- DAYMAR 88
- PILPNT 81
- M_QUAL Data quality 73
- BCNSPP Special purpose beacon 67
- PIPSOL 61
- BUISGL 53
- BCNLAT Lateral beacon 52
- BOYLAT Lateral buoy 51
- LNDRGN Land region 49
- LNDARE Land area 48
- OFSPLF 44
- RETRFL 41
- DRGARE 35
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/US4AL1BB.zip
- S-57 cell https://charts.openships.ai/noaa/s57/approach/US4AL1BB/12.0/US4AL1BB.000
- GeoJSON https://charts.openships.ai/noaa/s57/approach/US4AL1BB/12.0/US4AL1BB.geojson
- GeoParquet https://charts.openships.ai/noaa/s57/approach/US4AL1BB/12.0/US4AL1BB.parquet
- Metadata JSON https://charts.openships.ai/noaa/s57/approach/US4AL1BB/12.0/metadata.json
Editions
| Edition | Published | Metadata |
|---|---|---|
| 12.0 | Jun 9, 2026 | metadata.json |