Timezone database with Lat/Lng coordinates

I'm looking for a list of timezones with polygon lat/lng information. I want to build a tool that I can punch in a lat/lng and spit out a timezone. Basically the same thing that Geonames and EarthTools does except that I don't want to have to make a web service call or depend on a third-party service with request limits.

Any su开发者_运维百科ggestions on where I can find this data?

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Look this website.

http://www.geonames.org/

Have daily updates