403 in Controller Subdirectory access

This is some of my syntax in Routes file:

PHP Code:

$routes->add("admin", "Admin/Login::index");
$routes->add("login", "Admin/Login::index");
$routes->add("admin/home", "Admin/Admin::index"); 


And my folder structure for Controller is like :


Both this link is fine when I access it:

Code:

http://mydevsite.vhost/admin/home
http://mydevsite.vhost/login

But this link:

Code:

http://mydevsite.vhost/admin

Got a 403 forbidden, is this normal? how can I redirect user who access that link to somewhere else?