• The code (left out the CDATA section)

foreach my $id (keys %{$data}) {
    my $placemark = $dom->createElement('Placemark');
    my $name = $dom->createElement('name');
    $name->appendTextNode( $data->{$id}->{name} );

    my $style_url = $dom->createElement('styleUrl');
    $style_url->appendTextNode( '#' . lc($data->{$id}->{num}) . 
    'Style' );

    my $description = $dom->createElement('description');

    my $point = $dom->createElement('Point');
    my $coordinates = $dom->createElement('coordinates');
    $coordinates->appendTextNode( $data->{$id}->{longitude} . ',' 
    . $data->{$id}->{latitude} );

    $point->appendChild($coordinates);
    $placemark->appendChild($style_url);
    $placemark->appendChild($name);
    $placemark->appendChild($description);
    $placemark->appendChild($point);
    $document->appendChild($placemark);
}