sajid, there have been some discussions on this "road trips".

I would suggest to you as a complimmentary info to take a look at them and get as much info as possible

http://www.qatarliving.com/search?cx=008937172676595728955%3A066rihafv68...

In the end the best choice is contacting the appropriate embassy (or agent) for full details on visas/permissions/insurance/costs

In this case KSA embassy or authorized agents in Doha, Qatar.

Embassy of the Kingdom of Saudi Arabia 4832030

Regards!!