The earthwork walls of Fort Niagara were reinforced with concrete and brick between 1863 and 1872 due to tensions with Canada over the U.S. Civil War. Tempers had cooled by 1872 and guns were not mounted. The walls, however, follow the lines laid out by the French in 1755.

Photo taken near the Sally Port.

"Sally ports" were a feature of castles and fortresses, a closely-guarded opening or door in the wall of a fortified building designed for the quick passage of troops. One of the primary uses of these doors was to mount quick attacks on whatever enemy army might be besieging the castle at the moment, and here's where we meet "sally." A "sally," from the Latin "salire" meaning "to jump," was originally a sudden rush out of a besieged position, a lightning attack designed to surprise the enemy. "Sally" in this original sense first appeared around 1560, and "sally port" is first found around 1649. "Sally" has since acquired the broader sense of "an excursion or escapade." And since castles and fortresses are in short supply these days, "sally port" has gradually come to mean any guarded doorway or opening.

The verb "Sally forth" means to set out in a sudden, energetic or violent manner.