use Archive::Tar;
chdir $ENV{'TEMP'} or die "Unable to chdir to $ENV{TEMP}\n";

my $tar = Archive::Tar->new;

#I then define $city, $category and $page_number

$tar->add_files("$city/$category/$page_number",
                "$city/$category/filedesc");
$tar->write('c:\files.tar');