Charles III gate with Tower of Homage in background, Fortaleza Ozama.

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This is the New World's oldest colonial military edifice. The site, at the meeting of the Río Ozama and Caribbean, was selected by Fray Nicolás de Ovando and construction began in 1502. Over the centuries the fort served as a military garrison and prison, flying the flags of Spain, England, France, Haiti, Gran Colombia, the US and the DR. Public tours began in the 1970s. Multilingual guides at the entrance charge around US$3.50 per person for a 20-minute tour.

As soon as you walk into the site, you’ll see the oldest of the buildings here: the impressive Torre del Homenaje (Tower of Homage). Its 2m-thick walls contain dozens of riflemen’s embrasures and its rooftop lookout offers 360-degree views of the city. To its right, solid and windowless, stands El Polvorín (the Powder House), which was added in the mid-1700s; look for the statue of St Barbara (the patron saint of the artillery) over the door.

Running along the fort's riverside wall are two rows of cannons: the first dates from 1570, the second was added in the mid-1600s. Both served as the first line of defense for the city’s port. The living quarters, now almost completely destroyed, were added along the city-side wall in the late 1700s. On the esplanade is a bronze statue of Gonzalo Fernández de Oviedo, perhaps the best-known military chronicler of the New World.