You can visit the Grand mosque and take pictures without problems,
but should make an appointment at least a day ahead at the entrance or via phone (Tel. 2418447 / 8).
You need to wear an abaya (a dress that covers your upper body and arms down to your toes), and a hejab (sort of a veil).
You can borrow this at the mosque.
There are also guided tours, offered by the Aware center almost every month.
You will get a little lecture about Islam and the history of the mosque at the beginning.
After that you can roam almost freely, just don't let the group out of you eyes or the guards will get a little nervous ;)
You see beautiful hallways and lamps
Beautiful carvings and interesting picture opportunities
The big prayer hall that fits around 10.000 people. It's huge!
The dome in the great hall, with all the names of Allah carved in there.
Beautiful ceilings
The mihrab. It shows the direction of the Qibla ( the direction Muslims pray in, facing the mosque in Mecca)
The room the Emir receives guests when he visits the Grand mosque for his prayers.
It has it's own entrance at the north west side of the mosque.
Chandelier in the Emir's room