Started Construction  1533 fort as we see it today began 1730 and completed in 1790

The Fort has six levels at 140 ft high

The reputation of being unconquerable and was the most feared of all the Spanish colonial fortifications! 

During the late 16th and early 17th century, the distinguished Italian military engineer  Juan Bautista Antonelli transformed El Morro from its original medieval tower shape to a thick-walled masonry stronghold capable of fully resisting the impact of cannon balls.

The construction  started 1608 fort as we see it today began 1730 and was completed 1783, although the majority of the renovations were conducted from 1765 to 1790

The largest fortification built by the Spanish in the New World. When it was finished in 1783, it covered about 27 acres of land and partly encircled the city of San Juan. Entry to the city was sealed by San Cristóbal's double gates. After close to a hundred years of relative peace in the area, part of the fortification (about a third) was demolished in 1897 to help ease the flow of traffic in and out of the walled city.

Between the years 1608 and 1610, a small wooden fort named Fort San Juan de la Cruz (or more often called “El Cañuelo,” which is Spanish for “small channel”) was built on a minor key at the entrance to the bay of San Juan opposite Castillo San Felipe del Morro

burned during the Dutch attack of 1625, and it was rebuilt with masonry but, by the early 1800s.

1639 The San Juan Gate was built as the entry to San Juan

Masonry walls fully encircled the city of San Juan by 1783

1586, nearly 50 years after the construction of Castillo San Felipe del Morro began; rudimentary masonry walls were set above those cliffs at the Sana Elena and the San Agustín batteries.