Victoria Falls, also Mosi-oa-Tunya, waterfall in south central Africa, on the Zambezi River, on the border between Zimbabwe and Zambia. The river, here more than 1.6 km (1 mi) wide, plunges 110 m (360 ft). A railroad bridge, completed in 1905, spans the gorge below the falls. The falls were named after British monarch Queen Victoria by Scottish missionary and explorer David Livingstone, who became the first European to see the falls in 1855.