The Castillo San Felipe de Barajas (San Felipe de Barajas Castle) is a fortress in the city. The castle is located in a strategic location, dominating approaches to the city by land or sea. It was built by the Spanish during the colonial era. Construction began in the year 1536, and it was originally known as the Castillo de San Lázaro, It was expanded in 1657.
As you know, South America during the Spanish invasion it was well known for having a lot of precious metal and gems. In Cartagena, you will be able to visit the museum that focuses on pre-Columbian relics, with 600+ gold, silver & ceramic pieces.
If you are interested, you can visit the Palace of Inquisition, also known as the Inquisition Palace from the eighteenth-century . It was the seat of the Holy Office of the Inquisition in Cartagena, now in modern Colombia. Finished around 1770, it currently serves as a museum showcasing historical artifacts.
If you want to go shopping - this is the place to go