Bir Mcherga is one of the delegations of Zaghouan Governorate. It is a transit point between the north, central, and southern regions. It covers about 594 km² and has both agricultural and industrial features. The area includes 8 imadas: Bir Mcherga City, Bir Mcherga Station, Dalayel El Arous, Ain Askar, Jebel Oust, Smenja, Boucha, and Ain Essafsaf.

Bir Mcherga Municipality is located north of the city of Zaghouan (the governorate capital). It covers 31,146 hectares and had a population of 14,604 according to 2014 statistics.