Opposite the Bridge of Lions, in the heart of downtown, the expansive, grassy Plaza de la Constitution, a former marketplace, has a gazebo, a couple of cannons and a Civil War memorial, as well as the remains of the town well. It was the central market for food, but also for slaves.

Other historic remains include the Old City Gate, at the northern end of St George St, built in 1739 to defend the northern St Augustine line from British attacks; and the Rosario Defense Wall (opposite the Huguenot Cemetery), a re-creation of a section of the original Spanish-built earth barrier - spiky yucca plants and prickly-pear cacti along the top successfully fended off the Brits.