Puerta de Alcala of Madrid
The Puerta de Alcala (Alcala gate, in english) gets its name because it is the start of the road leading to the town of Alcala de Henares.
In 1759 Carlos III following his entry to Madrid decided to knock down the old gate as it wasn’t to his taste and made a new one in its place. It became the main entrance to the town and one of the most representative monuments of his reign.
It was inaugurated in 1778, not as a monument, but as a royal door.