WCF Composite Services -

Hi, Can some one shed some light on WCF Composite services, basically I am trying to get one service , which will return all the related information in single service. For eg, a single WCF service will provide all the list of countries, all the cities for the countries, all the tourist spots with in those cities.
So in the implementation, I will be making a single service request, which will be returning all the above details in single request.
Thanks
PD
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