Tomas I used your advice and built a map of SA with sea successfully. When building SA from one tile, the sea is correct with only some islands drowned, (I download Africa from geofabrik and extract southern Africa from it with splitter because geofabrik SA cuts the coastline at the country border and not at the tile border.) When I build SA from 4 tiles (Windhoek; Jhb;Durban;Capetown) the sea and land is reversed in some tiles, and correct in some. I guess some splits in the coastline made by splitter does not get merged again / correct by mkgmap? BennieD ##################################################################################### Scanned by MailMarshal - Marshal's comprehensive email content security solution. Download a free evaluation of MailMarshal at www.marshal.com #####################################################################################