Qatar–Saudi Arabia border
The Qatar–Saudi Arabia border is 87 km (54 mi) in length and runs from the Gulf of Bahrain coast in the west to the Persian Gulf coast in the east. == Description == The border begins in the west at the Gulf of Salwah, proceeding overland via 4–5 straight lines (maps differ on the precise depiction) which forms a broad arc, terminating in the east at the Khor Al Adaid coast.
Source: Wikipedia — Qatar–Saudi Arabia border (CC BY-SA 4.0)