1820-1890
Decreased dependence on Spain due to a cultivation of various (both legal and illegal) trade partners. As San Juan is the only natural protected harrbor on the island, the increased trade resulted in a leap in commercial and industrial growth in the capital.
A new commercial core began to emerge along the Avenida Ponce de Leon, the road that connects Rio Piedras to San Juan. Here, the land was cheaper than on the peninsula near Old San Juan, and there was adequate transportation to the port facilities.
The city continued to experience high death rates that were caused by a lack of attention to issues of sanitation. In 1890, cisterns were still used to gather rain water for household uses and tuberculosis was rampant even among the wealthiest citizens.
*In 1897 San Juan's walls were torn down, just one year before American troops attacked.