<?php
/**
 * Template name: All Images
 */

// Get the header
get_header();

// Image attachment query arguments
$images_query_args = array(
    'post_type' => 'attachment',
    'post_status' => 'inherit',
    'post_mime_type' => 'image'
);
// Query image attachments
$images_query = new WP_Query( $images_query_args );

// Image attachment query loop
if ( $images_query->have_posts() ) : while ( $images_query->have_posts() ) : $images_query->the_post();

    // Output the attachment image
    wp_get_attachment_image( get_the_ID(), 'thumbnail' );

endwhile; endif;

// Be kind; rewind
wp_reset_postdata();

// Get the footer
get_footer();
?>