The Eastern Province (ash-Sharqiyah) is the largest province in Saudi Arabia, covering the entire Gulf coast of the country as well as the Saudi parts of the vast Empty Quarter.
The three main cities of the Eastern Province are all tightly clustered together and no more than a 15-min drive apart from each other.
The rest are scattered around the coast:
Dammam's airport (IATA: DMM) has services from around Saudi Arabia and limited international flights to major cities in the region. Flying in via Bahrain is also a viable option.
There are four trains a day from Riyadh to Dammam via Hofuf.
The King Fahd Causeway connects Khobar to Bahrain.
Public transport is very limited, so having your own wheels will really pay off here.
You can find various activities and things to do in Eastern Province. Some of the most popular activities in the area are related to dessert and sand sports, such as camping, quad safari and hiking. Other popular activities are the ones that focus on enjoying the clear water, fishing, boat trips and diving.
You can find all kinds of cuisine here. You find a lot of Indian and Pakistani restaurants. Finding standalone vegetarian restaurants is impossible. A delicacy in Saudi Arabia that you should try is dhub. Dhub is a delicacy among the Arabian Bedouins. You can either boil it or roast it and serve it with rice. Most of the meat can be found in its armored tail. In English it's commonly referred to as the spiny tail lizard (Uromastyx microlepis).
Like the rest of Saudi Arabia, pork is banned. If foreigners sneak pork in the province however, you could get into severe trouble with the authorities. So don’t expect any bacon or sausages on your travels in hotels and restaurants.
Alcohol is strictly forbidden in the Eastern province like the rest of Saudi Arabia. Heavy penalties and a prison sentence could apply or foreigners will get deported.
Always carry a bottle of water with you in the desert as temperatures can reach over 40 degrees or sometimes 50 Celsius. Fruit juice and soda are popular with locals too.
Carry your passport/work permit all the time. You can asked to produce your documents any time of the days and night. Do not point your camera at a lady. Do not carry alcohol/drugs into Saudi Arabia. Avoid carrying medicines unless you have a prescription along with it. Do not carry any pornographic material with you.