Clivia are a form of lily, commonly known as Natal lily or bush lily. As you might guess from these names, they are native to southern Africa. Specimens were collected by the British explorers William Burchell and John Bowie in 1815 and 1820, respectively. Clivia nobilis became the first named species when in 1828 the Kew botanist John Lindley named it in honor of Charlotte Percy (née Clive), Duchess of Northumberland (1787–1866), who was for a time the governess of the future Queen Victoria. (source: Wikipedia)
Here in Sydney, they are popular in public parks and in front of buildings, generally seen massed in borders and clumps. They flower late winter to early spring.
Clivia also comes with yellow flowers, but they are less common (in Sydney, at least).