One way: 

c:\@Work\Perl\monks>perl -wMstrict -le
"use List::MoreUtils qw(uniq);
 ;;
 use Data::Dump qw(dd);
 ;;
 my $hashref = {
   'Alabama' => [
     qw(Andalusia Anniston Clanton Eufaula Auburn Bessemer
       Eufaula Auburn Bessemer)
     ],
   'California' => [ qw(Barstow Barstow) ],
   'Georgia'    => [ qw(Darien) ],
   'New York'   => [
     'Coney Island', qw(Amsterdam Beacon Becon), 'Coney Island',
     ],
   };
 ;;
 make_uniq($hashref);
 dd $hashref;
 ;;
 ;;
 sub make_uniq {
   my ($hr) = @_;
   ;;
   $_ = [ uniq @$_ ] for values %$hr;
   }
"
{
  Alabama    => [
                  "Andalusia",
                  "Anniston",
                  "Clanton",
                  "Eufaula",
                  "Auburn",
                  "Bessemer",
                ],
  California => ["Barstow"],
  Georgia    => ["Darien"],
  "New York" => ["Coney Island", "Amsterdam", "Beacon", "Becon"],
}

[download]

Update: See List::MoreUtils::uniq()

Give a man a fish:  <%-{-{-{-<

In reply to Re: Hash Multiple values for a key-Filtering unique values for a key in hash by AnomalousMonk
in thread Hash Multiple values for a key-Filtering unique values for a key in hash by rahulme81

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