Cite Are you a geography genius? Rivers and LakesGeography Quiz Country CapitalsContinentsMountainsRivers and LakesFlagsOf the three rivers below, which is longest? MississippiDanubeAmazonLake Ontario is the source for which river? OhioSt. LawrenceYukonThe course of which river features the world's highest waterfall? a tributary of CaroniZambeziNiagaraWhat is the world's second-largest lake? SuperiorVictoriaOnegaWhich ocean features the greatest known depth? Caribbean SeaIndian OceanPacific Ocean Flags More Features ! Download Poptropica and play for free!Explore a limitless universe of uncharted islands See also: Are you a geography genius?