Area and it is the second largest in population size within it. Athens Urban Area The Athens Urban Area (), also known as Urban Area of the Capital () or Greater Athens (), today consists of 40 municipalities, 35 of which make up what was referred to as the former Athens Prefecture municipalities, located within 4 regional units (North Athens, West Athens, Central Athens, South Athens); and a further 5 municipalities, which make up the former Piraeus Prefecture municipalities, located within the regional unit of Piraeus as mentioned above. The Athens Municipality forms the core and center of Greater Athens, which in its turn consists of the Athens Municipality and 40 more municipalities, divided in four regional units (Central, North, South and West Athens), accounting for 2,597,935 people (in 2021) within an area of . Until 2010, which made up the abolished Athens Prefecture and the municipality of Piraeus, the historic Athenian port, with 4 other municipalities make up the regional unit of Piraeus. The regional units of Central Athens, North Athens, South Athens, West Athens and Piraeus with part of East and West Attica regional units combined make up the continuous Athens Urban Area, also called the "Urban Area of the Capital" or simply "Athens" (the most common use of the term), spanning over , with a population of 3,041,131 people as of 2021. The Athens Urban Area is considered to form the city of Athens as a whole, despite its administrative divisions, which is the largest in Greece and one of the most populated urban areas in Europe. Athens metropolitan area The Athens metropolitan area spans within the Attica region and includes a total of 58 municipalities, which are organized in seven regional units (those outlined above, along with East Attica and West Attica), having reached a population of 3,722,544 according to the 2021 census. Athens and Piraeus municipalities serve as the two metropolitan centres of the Athens Metropolitan Area. There are also some inter-municipal centres serving specific areas. For example, Kifissia and Glyfada serve as inter-municipal centres for northern and southern suburbs respectively. Demographics Population in modern times The Municipality of Athens has an official population of 637,798 people (in 2021). The four regional units that make up what is referred to as Greater Athens have a combined population of 2,597,935. They together with the regional unit of Piraeus (Greater Piraeus) make up the dense Athens Urban