Ciudad Lerdo (Lerdo City) is a small city in the northeastern portion of the Mexican state of Durango. It serves as the municipal seat for the surrounding municipality of the same name.It is located at co-ordinates 25.33° N, 103.31° W, bordering southeastern Coahuila. As of 2010, the city of Lerdo had a population of 79,669, up from 71,373 people as of 2005. Lerdo Municipality had a population of 141,043. The municipality has an area of 1,868.8 km² (721.5 sq mi).