River Street is about 2 miles long along the Savannah River, according to Wikipedia. The south side has rows of former cotton warehouses, some dating from the 1850s.
Factors Walk is built on the middle level of the sloping bluff, with warehouses beneath and Bay Street above. Cotton brokers, called factors, bargained there. The name Factors Row preserves the industry's name.
The pavement is Belgian block with streetcar tracks set in. Large tankers and container ships heading to and from the Port of Savannah sometimes pass within yards of the promenade.