During the 18th century St. Augustine functioned as a presidio, or Spanish military outpost, with forts and defensive lines protecting the city. The Rosario Line was one of these defensive lines. It was also known as the Line of Circumvallation.

This primarily earthen defense line was constructed in the early 1720s. It went west from the Castillo de San Marcos to the Maria Sanchez River, along what is today Cordova Street, then followed the Maria Sanchez creek south to current day San Salvador Street, turning east and ending near the Matanzas Bay.

The Rosario Line was named for the El Rosario Redoubt located behind the Government House used in the 18th and 19th century. The coquina foundation was between three and four feet wide in an arch shape. The artifacts, a fragment of olive jar and a fragment of green-glazed coarse earthenware, date to the first Spanish period, the time of construction. In 1761, the governor ordered a firing platform, the location of the cannons, to the redoubt. Among the remains found, a creamware potsherd, a glazed olive jar potsherd, and a patinated bottleneck, all dated to the renovations. The line fell into disrepair in the 1770s.

At another location on San Salvador Street, a subterranean duct was found. It consisted of two parallel, upright coquina stones on top of a brick surface. Within this duct grape, watermelon, and squash seeds were discovered. The duct could have been used to control runoff, to remove latrine or leather worker waste.

There are no visible remains of the Rosario Line, however, in the garden behind the governor’s house a plaque marks the location of the remains.

Researched, written, and narrated by University of West Florida Public History Student Kelcie Lloyd

Credits and Sources:

Kelcie Lloyd, University of West Florida