At the beginning of 2009, Israel had a population of 7.4 million residents. Where do they live? The most densely populated area is central Israel - the Central and Tel Aviv districts, where three million people resided; northern Israel - the North and Haifa districts, had 2.1 million residents; southern Israel - the Southern district, which includes the southern coastal plain, had 1.1 million residents; the metropolitan Jerusalem area had 910,000 residents; and the West Bank had 290,000 Jewish residents. The youngest population was in the West Bank, where the median age was 20.5 (half the population is younger than the median age and half is older). Central Israel had the oldest population, with a median age of 33.8 in the Tel Aviv district and 30.7 in the Central district. The median age in Jerusalem's district was 23.2. Israel's population is divided among more than 1,100 localities, but the majority of Israel's population resides in 228 urban localities and the rest in rural localities. About half of Israel's urban residents (3.2 million) are clustered in 14 cities with populations exceeding 100,000 residents. Jerusalem is the largest city in Israel, with a population of 764,000; but the Tel Aviv metropolitan area (known as the Tel Aviv district), an urban agglomeration that includes several adjacent cities without functional administrative boundaries, is larger, with a population of 1.2 million residents.