Travelling from Al Kharj to Dammam

Can anyone tell me the quickest route from Al Kharj to Dammam by road and the approximate time it wil take ? Also is it better done in daylight and is any of the road fenced off like the Riyadh -Dammam road. I would be concerned about camels crossing the road at night

Al-Kharj to Riyadh City Center  approximately 45 mins to 1 hr.
Riyadh to Dammam - approximately 4 hrs.

It is safe to travel at night. We prefer to do so. Just be careful of these reckless drivers.
Don't worry about the camels... they are not on the road at night. Camels are sleeping. :D

have a safe trip!