Is it possible to route a subdomain to specific template group? We are looking for a way to route a subdomain to a specific template to use as a landing page.

Is there a way to do this without routing through index.html and redirecting to the specified template folder and file?

I can confirm that using the redirect does lose some of the user information, tracking codes etc. However it does retain the referral url from the 3rd party site.
For this example we have two domains:

http://www.example.com
http://subdomain.example.com


To use different templates for the subdomain, we can accomplished this with these steps:

1) Setup subdomain to point to a different directory on your server:

Domain: /home/wherever/public_html
Sub-domain: /home/wherever/public_html_subdomain


2) Copy your index.php file over to your new subdomain directory and update the CRAFT_TEMPLATES_PATH variable to point to the location you want to have your templates.  In this example, both template folders are above web root.

// index.php for domain
define('CRAFT_TEMPLATES_PATH', realpath(dirname(__FILE__) . "/../templates").'/');

// index.php for subdomain
define('CRAFT_TEMPLATES_PATH', realpath(dirname(__FILE__) . "/../templates_subdomain").'/');


Your template folders now look like:

/home/wherever/public_html
/home/wherever/public_html_subdomain
/home/wherever/templates
/home/wherever/templates_subdomain