Puerta de alcalá, located in the centre of Madrid, on Independence square next to the Park of Buen Retiro, is one of the main monuments of the city.

The first gate of Alcala were built in 1598 by order of king Philip III in honor of the arrival in Madrid of his wife, Queen Margaret of Austria. The composition of the first gate consisted of a Central arch, decorated on top of a stone statue of the virgin Mary, and small outbuildings on both sides of it. The Alcala gate were some of the main gate in Madrid, all of these gates was five.

Almost two centuries later, in 1769, king Charles III decided to demolish the old gate, we can construct in their place a new, wider and greater than the previous one, which had become the symbol of renewed Madrid. A large number of famous architects of the time took up the development of new projects of the monument. But in the end won the project of the architect Francesco Sabatini. The opening of the new gate, which mixes two styles – Baroque and classicism, was held in 1778.

Gates are constructed from granite stone with five bays, the three Central span with semicircular arches, and two lateral rectangular shape. The facades of the buildings are decorated with pilasters, columns, sculptures of a lion's head and the four virtues – Wisdom, Justice, Courage and Moderation. Above the Central arch bears the inscription "Rege Carolo III. Anno MDCCLXXVIII", which translates from Latin as "King Charles III, 1778".