Spiked and studded dog-collars derive from the days of the Ancient Greeks, who would give their sheep-dogs sharply spiked collars to protect their necks from wolves whilst they watched over a Sheppard's flock at night.

Lions in the wild live for around 12 years.

The world's first underground was the London Underground in1863. It has 275 stations and 253 miles of track.

AMAZING FACTS