I'm not sure where you are from but it appears visas are for maximum 90 days and they don't have a multiple entry visa - just single entry or double entry.
Given the unstable political situation in the country you might be well advised to postpone your visit until such time as the country is a little more stable.
The Australian government for example has a DO NOT TRAVEL warning for Syria, which it only issues for a handful of the most unstable and dangerous countries.
The implications of this are that no travel insurance company (World Nomads included) will cover you if you still choose to go there. You are on your own.
Be warned. about 4 years ago