Atlantico (Spanish: Atlántico) is a department of Colombia. It is the third smallest, after San Andres and Quindio, with an extension of 3,388 sq km (1,308 sq mi). It has a population of 2,272,170 inh., making it one of the most densely populated departments in the country, with 670.65 inh./sq km (1737.1 inh./sq mi). Its capital is Barranquilla