Hi all, There's an interesting audio interview with Tyler Bell on O'Reilly Radar about how to specify geographical location. In the interview, Tyler talks about Yahoo's approach: http://radar.oreilly.com/2009/04/where-20-preview---tyler-bell.html In brief, they define a unique 32-bit number to each location: the "Where On Earth ID" or "WOEID". They also provide a public, restful API to query their database to extract metadata about the area. Details are available here: http://developer.yahoo.com/geo/ http://developer.yahoo.com/geo/guide/ One of the nice features of this is one can express low-granularity information (such as a city, county or country) without having to specify a (potentially meaningless) centroid lat./long. ordered pair. This is nice as they also expose their semantic structure, so one can (for example) discover that Canada is within the United States. I propose in the next version of GLUE we add an optional field called woeid so people have a standard field to include the WOEID, if they choose to do so. Cheers, Paul.