Estuary of a river is a maritime water body. Then my tagging natural=coastline is correct and you tagging waterway=riverbank is incorrect.

You have deleted natural=coastline from shoreline of Isla Látimer and part of Isla Madre de Dios. Now Isla Látimer has disappeared from mapnik rendering and Isla Madre de Dios has been "cutted". I think I said natural=coastline tag only can be used in segments, not in nodes neither relations. The wiki info is clear. Please more careful the next time. And source=PGS should not be shifted from the coastline segment to multipolygon relation.
Regards.

I remove tags from the ways of the relation, because the info is already inside the relation. Tagging both, ways and relations is redundant, except for tag natural=coastline and source=*.

Please don't add nodes to a multipolygon. It only accepts ways as members.

Can you tell me which is the Iris Island? I think this is a peninsula.

You should not remove natural=coastline tag from a way tagged as place=island or place=islet, because it will disappear from the map.

Already exists a multipolygon for Isla Duque de York. You should not put the name in outer rings of the multipolygon (on the coastline). It doesn't produce any effect or can produce an undesired effect.
Before put name to a island you should verify if the coastline is part of a multipolygon tagged as place=island.

@Rub21
El tema del render es algo secundario. Esa es la posición correcta de la línea de base, no así la de la línea de costa. De hecho, el Institutio Geográfico Nacional Argentino sitúa la línea de costa en la ciudad uruguaya de Carmelo aproximadamente, al igual que la International Hydrographic Organization.
Saludos.

boundary=administrative tag should not be used to delimit national parks and nature reserves.

Hello Michael.
The placement of the coastline in the same place of straight baseline is wrong. Straight baselines and coastline cannot match by definition. Coastline is a natural feature, therefore it cannot be changed by a law or treaty. It only can be changed by a man-made structure as Afsluitdijk in Netherlands or any breakwater.
River Plate is clearly not continental waters. It's a sea-level water body and flooded directly by the sea. River Plate is an estuary and estuaries are marine environments.

Here you have two differents sources about the worldwide coastline compress in a shapefile and you can see the great mistake:

https://www.ngdc.noaa.gov/mgg/shorelines/data/gshhg/latest/

http://www.naturalearthdata.com/downloads/10m-physical-vectors/10m-coastline/

Please rethink your changeset.
Regards.

I would be grateful to you if you are capable to do it. There is an user who created all chilean maritime boundaries. You can see quality of them is very fine, generated by a script. I wrote to him a while ago. He was disposed to share his script, but he forgot to answer me again. Maybe you can write him about this again.

Here is his changeset: changeset/4232326

or: changeset/4233145

Regards.

Hello Martien,
in this changeset I only made fixes in the Chile-Peru maritime border.
Apparently the change that you refer was made by the user "4rch".
But this is clearly wrong, because Peru don't exercise territorial sovereignty outside 12 nautical miles and there are international laws about that.
If you can create a boundary that reach 12 nm from Peru coastline you can fix this issue.
Regards.

You can see the discussion here: changeset/33040192

Thanks for the observation. Old limit was in the mouth of the river.

Thanks for the info.

I have understood the 2 m value is the height above "mean" sea level. But, natural=coastline is set approx in the high water mark and here tidal range is big. This is my doubt.

Hello, looking satellite imagery it seems Baker Lake is really an enclosed maritime bay instead a freshwater non-maritime body.

Here there is an unconnected coastline segment: http://tools.geofabrik.de/osmi/?view=coastline&lon=-81.50004&lat=52.32722&zoom=16&opacity=1.00&overlays=coastline,coastline_error_lines,line_not_a_ring,line_overlap,line_invalid,line_direction,questionable,coastline_error_points,unconnected,intersections,not_a_ring,double_node,tagged_node

Hola, el cambio que hiciste en el límite internacional es incorrecto. El Tratado de 1982 dice que el límite internacional en la boca oriental del Estrecho de Magallanes es una línea recta que une los hitos de Punta Dungeness con el del Cabo Espíritu Santo. Incluso había una nota que creo no leíste. Lo he vuelto a corregir. Saludos.

Ok, but must be careful to add every island to multipolygon as inner ring to avoid a "flooding". I add recently like twenty islands mapped previously, but was not part of the relation.

changeset/33818750