The statue of King Carlos III was placed here in 1997, right across the building with the white and red stones, Casa de Correos. It commemorates a smart and revolutionary king who did a lot for the advancement of the Spanish Kingdom and Empire, making it an educational place, modern and industrialized.
And so, Carlos was crowned King of Spain in 1759, after the death of his half-brother, Fernando VI. This is when his name officially changed to Carlos III, and he ruled Spain until 1788.
As a king, Carlos III was very active in the political scene, and handled close international relations with France and England, especially during power battles over English colonies in the Americas. He supported France in the Seven Years War, and lost Florida to England. France then compensated Spain with French Louisiana. Carlos fought back against Britain, by giving support to the rebels in colonial lands in the New World. He knew that this support endangered his rule in the Spanish territories of America, but he took a calculated risk and won. Britain was defeated in the American Revolution and lost its colonies in favor of American independence.
The same Carlos will continued to advance reforms in the kingdom, that began before his time, and were called The Bourbon Reforms. This was a line of reforms that were meant to place Spain and its Empire in a new era, in a time of enlightenment and education, that then began in Europe.
Carlos also improved the sewage system in Spain, and industrialized the Spanish Kingdom, even though he has not very successful. He promoted free trade in the Spanish Empire, and made many reforms for taxes. Many Spaniards see him as one of the more successful kings who came from the royal line in the history of Spain.