diff --git a/wp-content/themes/twentyten/attachment.php b/wp-content/themes/twentyten/attachment.php
index 14fe382cbb..12c717de2a 100644
--- a/wp-content/themes/twentyten/attachment.php
+++ b/wp-content/themes/twentyten/attachment.php
@@ -68,10 +68,18 @@
 			break;
 	}
 	$k++;
-	if ( isset( $attachments[ $k ] ) )
-		$next_attachment_url = get_attachment_link( $attachments[ $k ]->ID );
-	else
-		$next_attachment_url = get_permalink( $post->post_parent );
+	// If there is more than 1 image attachment in a gallery
+	if ( count( $attachments ) > 1 ) {
+		if ( isset( $attachments[ $k ] ) )
+			// get the URL of the next image attachment
+			$next_attachment_url = get_attachment_link( $attachments[ $k ]->ID );
+		else
+			// or get the URL of the first image attachment
+			$next_attachment_url = get_attachment_link( $attachments[ 0 ]->ID );
+	} else {
+		// or, if there's only 1 image attachment, get the URL of the image
+		$next_attachment_url = wp_get_attachment_url();
+	}
 ?>
 						<p class="attachment"><a href="<?php echo $next_attachment_url; ?>" title="<?php echo esc_attr( get_the_title() ); ?>" rel="attachment"><?php
 							$attachment_size = apply_filters( 'twentyten_attachment_size', 900 );