Old San Juan is located on a small and narrow island which lies along the north coast, about 35 miles 56 km from the east end of Puerto Rico, and is united to the mainland of Puerto Rico by three bridges. It is bounded by the Atlantic Ocean to the north and to the south by San Juan Bay or "Bahia de San Juan" βwhich lies between the city and the mainland. On a promontory Spanish: morro about feet 30 m high, at the west end of the island and commanding the entrance to the harbor, rise the battlements of Fort San Felipe del Morro , in which there is a lighthouse.
The city is characterized by its narrow, blue cobblestone streets, and flat-roofed brick and stone buildings, which date back to the 16th and 17th centuriesβwhen Puerto Rico was a Spanish possession. The ruins of Caparra are known as the Pueblo Viejo sector of Guaynabo , behind the almost land-locked harbor just to the west of the present San Juan metropolitan area. In , the settlement was abandoned and moved to a site which was called at the time "Puerto Rico" meaning "rich port" or "good port" , a name that evoked that of a similar geographical harbor in the island of Gran Canaria , Canary Islands.
In , the name "San Juan" was added, and the newer settlement was given its formal name of "San Juan Bautista de Puerto Rico", following the usual custom of christening the town with both its formal name and the name which Christopher Columbus had originally given the islands, honoring John the Baptist. La Fortaleza was built between and , which was followed by the construction of a battery at "the Morro. Circumvallation of the city commenced in and was concluded by San Cristobal fort was completed by By , the population totaled , half of which were soldiers.
The garrison town of San Juan included acres of military installations and 62 acres of public and private use. By , the city's fortifications included cannon. By , 24, lived inside the walls of San Juan, encompassing 62 acres, and buildings. Prior to the 19th century, the area outside the city walls occupying the east side of Old San Juan Island, was almost uninhabited. In the so-called area of Puerta de Tierra or "Land Gate" had a population of residents, mainly of African descent.
On March 3, , the municipal government of San Juan approved a resolution promoting the city expansion across the Puerta de Tierra which included the plan for demolishing the city walls along the eastern side. During the late s, disrepair in the old city was evident. The local authorities were considering development proposals for renovating the old city and incorporating modern architecture on new constructions.
