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map.openseamap.org/

OpenSeaMap

Freeauth: noneODbL-1.0#osint#maritime#charts#openseamap#openstreetmap#harbours✓ verified Nov 5, 2026

OpenSeaMap

OpenSeaMap is a free nautical charting project built on OpenStreetMap that publishes sea marks, lights, harbours and related marine layers on an interactive map, with data held in the OpenStreetMap database under ODbL.

Required Attribution:

© OpenSeaMap contributors / OpenStreetMap

Coverage

Global volunteer-mapped nautical features where contributors have added seamarks and harbour data; coverage quality varies by region and is Not stated as a completeness percentage on the checked pages. Update frequency follows OpenStreetMap edits (continuous); a single official refresh SLA is Not stated.

Verdict

This is an open nautical-feature layer for agents that need harbour, buoy and light context next to AIS tracks — distinct from the general OpenStreetMap Planet dump already listed. OpenSeaMap's wiki states the data stand under ODbL, allowing commercial use when OSM attribution and share-alike rules are met.

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Use in your agent

Probe OpenSeaMap map and ODbL wiki licence note. Checked against the provider's documentation on Nov 5, 2026.

Raw skill file (/skills/openseamap.md)Also in our MCP server: call get_ingestion_skill with {"slug": "openseamap"}.

Access

  • No account for the public map and wiki licence page. Bulk geometry follows OpenStreetMap/ODbL export practices.

Request

bash
curl -I 'https://map.openseamap.org/'

Format

HTML map application; OpenStreetMap wiki licence section for OpenSeaMap.

Load into pandas and Parquet

Needs Python 3 with requests, pandas and pyarrow.

python
"""OpenSeaMap reachability + ODbL mention -> pandas -> Parquet."""
import pandas as pd
import requests

UA = {"User-Agent": "SignalLabCheck/1.0"}
rows = []
for url in ["https://map.openseamap.org/", "https://wiki.openstreetmap.org/wiki/OpenSeaMap"]:
    r = requests.get(url, headers=UA, timeout=60, allow_redirects=True)
    rows.append({"url": url, "status": r.status_code, "bytes": len(r.content), "mentions_odbl": "odbl" in r.text.lower()})
df = pd.DataFrame(rows)
df.to_parquet("openseamap_probe.parquet", index=False)
print(df)

Run by us on 2026-11-05 (python 3 | pandas | pyarrow | requests). Result: map.openseamap.org and the OpenSeaMap wiki page returned HTTP 200 on 2026-11-05; wiki text mentions the ODbL licence.

Limits

  • Not stated.
  • This skill does not download the full OSM planet or seamark extracts.

Quirks

  • OpenSeaMap is an OSM-based nautical layer, not a substitute for official ENC carriage.
  • ODbL share-alike and attribution apply to database extracts.

Terms and attribution

  • ODbL per OpenSeaMap wiki: commercial use allowed with OSM attribution and share-alike.

Sources

Information and education only. Not financial, investment, legal or tax advice. Listings can be inaccurate, incomplete or out of date and are provided "as is". Free tiers, limits and licenses belong to each provider and can change, so check the provider's own terms before you rely on them. Terms & Disclaimer

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