David Livingstone, the Scottish missionary and explorer, is believed to have been the first European to view Victoria Falls on 16 November 1855, from what is now known as Livingstone Island, one of two land masses in the middle of the river, immediately upstream from the falls near the Zambian shore. Livingstone named his discovery in honour of Queen Victoria of Britain, but the indigenous Tonga name, Mosi-oa-Tunya—"The Smoke That Thunders"—continues in common usage as well. The World Heritage List officially recognizes both names.
Source: Wikipedia