Geo::WebService::Elevation::USGS executes elevation queries against the United States Geological Survey's web server. You provide the latitude and longitude in degrees, with south latitude and west longitude being negative. The return is typically a hash containing the data you want. Query errors are exceptions by default, though the object can be configured to signal an error by an undef response, with the error retrievable from the 'error' attribute. WWW: http://search.cpan.org/dist/Geo-WebService-Elevation-USGS/