Passage: Britannia is a national personification of the United Kingdom, originating from Roman Britain. Britannia is symbolised as a young woman with brown or golden hair, wearing a Corinthian helmet and white robes. She holds Poseidon's three-pronged trident and a shield, bearing the Union Flag. Sometimes she is depicted as riding on the back of a lion. Since the height of the British Empire in the late 19th century, Britannia has often been associated with British maritime dominance, as in the patriotic song "Rule, Britannia!". Up until 2008, the lion symbol was depicted behind Britannia on the British fifty pence coin and on the back of the British ten pence coin. It is also used as a symbol on the non-ceremonial flag of the British Army.A second, less used, personification of the nation is the character John Bull. The bulldog is sometimes used as a symbol of the United Kingdom and has been associated with Winston Churchill's defiance of Nazi Germany.

Question: What kind of animal does Britannia ride?
lion