Danish to English Other Tourism & Travel

We're on St. Thomas in the Danish West Indies/U.S. Virgin Islands, and it may help if you know some Spanish as well:

"Mod vandsiden er fortet beskyttet af vandbatteriets kanoner."

My first inclination was "the shore battery" without capitalization. However, there's a U.S. government publication from 1925 that has this as:

"Water Battery; Shoreward outwork, or waterside trench, of Fort Christian, St. Thomas Harbor. Since eighteenth century, called, "Vandbatteri ” or “Water-Batterie”; Spanish “La Batería Water” or “Batería del Agua.”

There are other references to this location as "the water battery" or "a water battery" with and without capitalization.

From the 1925 reference I found this Spanish description for something similar in Puerto Rico:
"La primera estructura militar erigida en este promontorio data de 1539 y consistía en una torre de piedra construida contra el risco a unos 60 pies sobre el nivel del mar. Tenía cuatro troneras de cañón y una plataforma circular para tres piezas de artillería que se conocía con el nombre de ‘batería del agua’."

Now, from reading the Spanish I'm still inclined toward "the shore battery" but possibly with capital letters, but I fear I'll be sailing into the face of some resistance with that.

Anyone have any thoughts, however well-founded or not? Anybody been to the place in question and seen any signs?