Set up multiple views of a single template that appear as subpages in the URL (WordPress)

functions.php

function prefix_cpt_rewrite() {
	add_rewrite_tag( '%view%', '([^&]+)' );
}
add_action( 'init', 'prefix_cpt_rewrite' );

function prefix_cpt_rewrite_rules() {
	$slug = 'cpt-slug';
	$param_name = 'view';
	$param_val = 'map';

	add_rewrite_rule(
		$slug . '/([^/]*)/' . $param_val . '/?',
		'index.php?post_type=' . $slug . '&name=$matches[1]&' . $param_name . '=' . $param_val,
		'top' );
	add_rewrite_rule(
		$slug . '/([^/]*)/([^/]*)/' . $param_val . '/?',
		'index.php?post_type=' . $slug . '&name=$matches[2]&' . $param_name . '=' . $param_val,
		'top' );
}
add_action( 'init', 'prefix_cpt_rewrite_rules' );