Region is one of Tanzania's 30 administrative regions. The regional capital is the city of Dar es Salaam. According to the 2012 national census, the region had a population of 4,364,541, which was much higher than the pre-census projection of 3,270,255. For 2002-2012, the region's 5.6 percent average annual population growth rate was the highest in the country. It was also the most densely populated region with 3,133 people per square kilometer