According to the new self-governing law, referred as “KALLIKRATIS” since January 1, 2011 the municipalities of Nea Makri and Marathon and the Communities of Grammatiko and Varnavas were consolidated into a new municipality with the historic name of Marathon. The seat of the new municipality is the city of Marathon.
The new Municipality of Marathon is the fifth largest Municipality in the region of Attica and among the largest ones in Greece. Its population reaches the 33.423 inhabitants. It is located in the northeast coast of the prefecture of Attica.
At Nea Makri inhabit 16.670 people (49,9%), at Marathon 12.849 (38,4%), at Grammatiko 1.823 (5.5%) and at Varnavas 2.081 (6.2%).

The new Municipality of Marathon is managed by the Mayor and the City Council consisting of 33 members. There is also a Council of the Community of Nea Makri which consists of 11 members, a Council of the Community of Marathon which consists of 11 members, a Council of the Community of Grammatiko which consists of three members and a Council of the Community of Varnavas which consists of 3 members.