Several physiographic provinces are captured in this southeast-looking, high-oblique photograph. The large, dark green area on the west side of the photograph is the Nile River Delta, which extends from the capital city of Cairo at the apex of the delta to the Suez Canal on the eastern edge (the relatively straight line that runs north-south) to the city of Alexandria on the west corner (outside this photograph). The alluvial soils, which have been deposited by the Nile River for many centuries, provide a unique environment for the production of a variety of crops, and the flooding of the river makes up for lack of rainfall. The entire region is classified as desert [less than 10 inches (25 centimeters) of rainfall per year]. Desert-like sandy areas are visible southwest of the delta and in the northwestern part of the Sinai Peninsula. In addition to these sandy areas, major rock outcrops (darker areas) are seen encircling the Red Sea, including the southern two-thirds of the Sinai Peninsula. The darker, hilly terrain along the western shore of the Red Sea is the Arabian Desert, and the low mountains along the eastern shore of the Red Sea in Saudi Arabia are the Al Hijaz Mountains. The two elongated bodies of water flanking the southern end of the Sinai Peninsula are the Gulf of Suez (western boundary) and the Gulf of Aqaba (eastern boundary). The linear feature extending to the northeast from the northern end of the Gulf of Aqaba is the southern end of the Dead Sea Rift, which is part of the much larger East African Rift Valley that runs 6000 miles (9600 kilometers)—from the Middle East to south-central Africa. The faint line that can be seen along the eastern part of the Sinai Peninsula is the boundary between Egypt and Israel. The line is a result of different densities in vegetation.