Bay
Bay of Biscay
Natural Earth’s outline of the Bay of Biscay measures about 216,000 km² (83,400 mi²), the 25th largest of the 42 seas on sizeversus, and about the same size as Guyana.
200 km
- Bay of Biscay
- Guyana
The numbers
- 216,000km²Area, measured83,400 mi² · Natural Earth outline
- 223,000km²Area, publishedWikidata · 3.1% above our measure
- 4,735mGreatest depthaverage about 1,800 m
- 389,000km³VolumeWikidata
The area is measured from the outline drawn above, on the WGS84 ellipsoid; the published figure is shown beside it, and a water body is kept only if the two are within 10%.
What the numbers say about the Bay of Biscay
- The Arabian Sea, the largest of the 42 seas ranked on sizeversus, is 19.1× the size of the Bay of Biscay; the Bay of Biscay ranks 25th.
- The Bay of Biscay sits between the Molucca Sea (217,000 km²) and the Gulf of California (172,000 km²) in the ranking.
- Counted as a country, the Bay of Biscay would be larger than 129 of the 212 countries listed on sizeversus and would rank 84th by area, between Laos (228,000 km²) and Guyana (211,000 km²).
- It is larger than 37 of the 51 US states and districts (the biggest of them is Kansas, 213,000 km²) and smaller than 14.
- It is larger than 22 of the 31 provinces and regions of China (the biggest of them is Hunan, 211,000 km²) and smaller than 9.
- The closest US state is Idaho (216,000 km²): the Bay of Biscay is about the same size as Idaho.
- Wikidata records a greatest depth of 4,735 m; with its volume that gives an average depth of about 1,800 m.
- Wikidata records a volume of 389,000 km³. Poured over Romania (236,000 km²), that water would stand 1,646 m deep.
- On a standard web map (Web Mercator), a place at 46°N is drawn about 2.0× too large in area, so the Bay of Biscay looks bigger there than it is.
- Laid out flat, the Bay of Biscay stretches about 571 km north to south and 592 km east to west.
- Our measured 216,000 km² is 3.1% below Wikidata’s published figure of 223,000 km². Published areas of lakes and seas move with the water level and with what is counted, so a few percent is expected.
About the same size as
Countries
On the shore
Natural Earth’s outlines of France and Spain lie within 25 km of the outline of the Bay of Biscay. That is what its geometry says, and it is not a statement about who owns the water or where any border runs in it.
Where the Bay of Biscay ranks
The Bay of Biscay is the 25th largest of the 42 seas on sizeversus, ranked by measured area.
Compare the Bay of Biscay
Share this outline
Sources and method
- Outline
- Natural Earth, 1:10m Marine Areas (geography_marine_polys), public domain (Marine Areas (geography_marine_polys)). Natural Earth draws marine areas for labels and cuts them at named sub-areas; the outline is kept because its area matches the published one.
- Boundary
- A lake or a sea has no legal boundary of its own. The outline is a cartographic one, and the page says so by showing the measured area beside the published one.
- Area basis
- Measured outline: computed on the WGS84 ellipsoid from the full-detail outline and shown rounded. Published figure: Wikidata (CC0), fetched 2026-11-11. An outline is kept within 10% of the published figure and matched to other places automatically within 5%.
- Depth, volume, height
- As recorded in Wikidata; a volume that cannot be right for the area and depth is left out.
- Shore
- Countries whose Natural Earth outline contains or comes close to the water's outline; computed, not a statement of ownership.
- Drawing
- Each outline is projected with an equal-area projection centred on its own centroid, so areas stay true and two can be laid over each other.
- Data built
- 2026-11-11