It limits to the north and west with the canton of Alajuela, to the east with Flores and Heredia, and to the south with San José, Escazú and Santa Ana.

In 2011, the presence of Intel's high-tech industrial plant made Belén the canton with the highest competitiveness index in the country.

Important historical sites are the House of Culture (Built in 1908), and the old Pacific Railway station, as well as the Church dedicated to San Antonio de Padua.

By constructing an access road between the port of Puntarenas and San José, this place became a mandatory rest stop.

Initially, when it was just a small town, the canton was called Potrerillo, then Barrio de La Asunción, and later San Antonio.

The name Belén was given by Monsignor Joaquín Llorente y La Fuente, who coincidentally visited the place twice in consecutive years (1858 and 1859) and celebrated the Christmas Eve midnight mass there.

In Belén, there are also companies like Firestone, Amanco, Pipasa, EPA, Kimberly-Clark, Pedregal, Tribu, Belca, Lizano, Unilever, and Trimpot, among others.

Recently, a Hard Rock Café, the first of its kind in Costa Rica, was opened in the La Asunción district.

The same census details that the economically active population is distributed as follows: The compact canton is on the western side of the General Cañas Highway midway between the national capital city of San José and the Juan Santamaría International Airport.

The American International School of Costa Rica is located in Cariari, La Asunción District, Belén.