San Basilio is named after the saint to whom the parish of Nuestra Señora de la Paz (Our Lady of Peace) was dedicated.

At the beginning of the 15th century, it was decided to combat the city's lagging population by accommodating crossbowmen and their families there, especially as they could also man the surrounding defences.

Unlike the winding streets elsewhere in the city centre, they are perfectly straight, introducing a more rational approach to urban planning.

[3] One of the most interesting structures in San Basilio is the Torre de Belén, a fine example of a former defensive gate providing access to a walled enclosure.

The parish Church of San Basilio, on the site of a monastery founded in 1590, is built in the 17th-century Baroque style with period furnishings.