Beirut was the capital and largest city of Lebanon. As of 2014, Greater Beirut had a population of 2.5 million, which makes it the third-larges…Beirut was the capital and largest city of Lebanon. As of 2014, Greater Beirut had a population of 2.5 million, which makes it the third-largest city in the Levant region and the thirteenth-largest in the Arab world. The city was situated on a peninsula at the midpoint of Lebanon's Mediterranean coast. Beirut had been inhabited for more than 5,000 years, making it one of the oldest cities in the world.