Victoria Falls are not subtle. The Zambezi River drops 108 metres across a basalt lip 1.7 km wide into a narrow chasm, creating the world's largest sheet of falling water and a spray column visible from vast distances. The roar is audible well before you see anything. In full flood (February to April) the volume of water is so great that the gorge below fills with spray and you can barely see the falls at all — which is itself a spectacle of a different kind.
From the Zambian side, the access is through Mosi-oa-Tunya National Park. The main viewpoints look across to the Zimbabwean side and into the gorge below; the Knife's Edge bridge offers vertiginous close-up views of the Eastern Cataract. The famous Livingstone Island, in the centre of the Zambezi just above the falls, can be visited in low water season — guides take you across by boat to swim in the natural pool at the very lip of the falls, which is an extraordinary and slightly alarming experience.
Bring a waterproof bag and a change of clothes; the spray drenches you thoroughly at most viewpoints.