// Read data into memoryvardata=GeoFileReader.ReadExtendedGeoNames(@"D:\foo\cities1000.txt").ToDictionary(p=>p.Id);// Find New York by it's geoname ID (O(1) lookup)varnew_york=data[5128581];// Find 10 nearestvarr=newReverseGeoCode<ExtendedGeoName>(data.Values);r.NearestNeighbourSea...