0> In article <5175AA64-611C-44BB-AA72-DC87DBB3EB6E@googlemail.com>, 0> Clinton Gladstone <URL:mailto:clinton.gladstone@googlemail.com> ("Clinton") wrote: Clinton> I think this option [--generate-sea] still needs to be refined. Clinton> I have downloaded coastline extracts and specially processed Clinton> them (for a separate sea layer), and have had similar problems. Clinton> The data I was working on did not need to be split, so I think Clinton> you can rule the splitter out as being part of the problem. Clinton> Clinton> It seems that under certain circumstances the generate-sea Clinton> option inverts land and sea. Thanks. I've not used osmosis before, but it appears it can extract the coastline for separate processing, so I should be able to create smaller extracts to experiment with. Then I can look into the code myself. (But not today; it's too nice to stay indoors!)