I noticed that the timezone returned by the timezone service, doesn't always return the correct value for places close to the Dutch coast line. For example, a part of Bergen op Zoom is thought to be in the sea: http://ws.geonames.org/timezone?lat=51.478414&lng=4.27894 On my website this can be verified, because the place of which the timezone data is retrieved, is also visible on a Google Map: http://www.transitofvenus.nl/times.html?lat=51.478414&lon=4.27894&y=2012 I don't know if this can be fixed, but I think it would be better if points at the large water surfaces in the Netherlands have the same timezone as the main land.