#!/usr/bin/perl
use warnings;
use strict;
use feature qw{ say };

use XML::Twig;

my $header;
my $twig = 'XML::Twig'->new(
    twig_handlers => {
        h3 => sub { $header = $_->text; $_->purge; },
        'div[@class="event"]' => sub {
            say $header, "\t", $_->text;
            $_->purge;
        },
    },
);
$twig->parsefile('file.xml');