María Agustina Square is one of the main public spaces in Castellón de la Plana. It was built in 1886 and takes its name from María Agustina, a freed Black enslaved woman who worked as a servant in the home of the local countess, making it a unique case in Spanish urban nomenclature of the period.

The most characteristic and iconic element of the square is a century-old ficus tree, a monumental tree of local interest that has received public recognition. A plaque commemorates the Tree Festival celebrated around this specimen, which occupies a large planter in the centre of the space.

Surrounding it are some of the most important political institutions in the province of Castellón. Number 1 on the square houses, amongst others, the institutional headquarters of the Consell de l'Audiovisual de la Comunitat Valenciana (CACV), which reinforces its character as an administrative and civic hub for the city.

The square constitutes one of the nerve centres of Castellón de la Plana's urban centre, with pedestrian connections to other historic spaces in the city. It is also the starting point for hiking routes to surroundings such as La Magdalena.

The history of the square's name represents a unique testimony of urban historical memory: the vindication of the memory of a woman of African origin in the street names of a 19th-century Spanish city, a fact that gives it added cultural and symbolic value.