Portrait of Juan de Herrera.

Juan de Herrera (1530–1597) was a Spanish architect, mathematician and geometrician. One of the most outstanding Spanish architects in the 16th century, Herrera represents the peak of the Renaissance in Spain. His sober style was fully developed in buildings like the Monastery of San Lorenzo de El Escorial. The Herrerian style was named after him, and was representative of the architecture of the Spanish Empire of Philip II and his Austrian successors.

As a Renaissance man, Herrera was interested in all the branches of knowledge of his times. His Discurso sobre la figura cúbica (Discussion of the Cubic form) tells us about his notable knowledge about geometry and mathematics. He also participated in the military campaigns of Charles V in Germany, Flanders and Italy.

Depicts El Escorial and denomination.

The Royal Site of San Lorenzo de El Escorial (Spanish: Monasterio y Sitio de El Escorial en Madrid), commonly known as El Escorial, is a historical residence of the King of Spain, in the town of San Lorenzo de El Escorial, about 45 kilometres (28 miles) northwest of the capital, Madrid, in Spain. It is one of the Spanish royal sites and has functioned as a monastery, basilica, royal palace, pantheon, library, museum, university and hospital.

El Escorial comprises two architectural complexes of great historical and cultural significance: the royal monastery itself and La Granjilla de La Fresneda, a royal hunting lodge and monastic retreat about five kilometres away. These sites have a dual nature; that is to say, during the 16th and 17th centuries, they were places in which the power of the Spanish monarchy and the ecclesiastical predominance of the Roman Catholic religion in Spain found a common architectural manifestation. El Escorial was, at once, a monastery and a Spanish royal palace.

The building's cornerstone was laid on 23 April 1563. The design and construction were overseen by Juan Bautista de Toledo, who did not live to see the completion of the project. With Toledo's death in 1567, direction passed to his apprentice, Juan de Herrera, under whom the building was completed in 1584, in less than 21 years. To this day, la obra de El Escorial ("the work of El Escorial") is a proverbial expression for a thing that takes a long time to finish.

A smooth edge separated into equal sections by seven indents (Spanish flower)