Each city has its stone, some architectural peculiarity that its buildings share, and that is one of the hallmarks of its urban landscape. In Cadiz, one of the cities that we visit the most with our tours, that particularity, is the ostionera stone, which is located in many of its old buildings and widely in its walls and bastions. When we walk through its streets we see it constantly and it draws attention to its composition that confirms that Cadiz emerges from the sea.

Specifically the ostionera stone is the local name of a very porous sedimentary rock formed by remains of seashells and eroded stones of the sea. The stone was extracted from towns near Cadiz, such as Puerto Real, El Puerto de Santa María, Rota or Chipiona and was very important not only in the construction of buildings in Cadiz but in other Andalusian cities such as Seville in which it is very present in the cathedral.

In this architectural aspect the great poetic of Cadiz is that it rises on the same stone on which it sits. The city sits on a large stone platform ostionera that emerged from the ocean thousands of years ago forming two islands, Eryteia or La Roja, and Kontinousa or Isla de los Acebuches. On one of them the Phoenician sailors carved Gadir, and on the other rose the Roman Gades.

Many historic cities were sculpted from lands emerging from the sea, men built their palaces, walls and houses with the rise. Many of them, also disappeared later, others like Cadiz or as Valletta in Malta, are alive and it is an obligation to visit them and dive into the taste that leaves their marine history in its streets and buildings.

The ostionera stone can still be purchased today from local quarries in the area that continue to sell it. Although its use is much less than in the past, it is still part of the local Architecture of Cadiz and Andalusia. In this photo, the Cathedral of Cadiz, one of the oldest buildings in the city of Cadiz. Its underside was built entirely of ostion stone.