When music fans think of "the British Invasion" they are referring to '60s bands like The Beatles and The Rolling Stones. Britain today, however, faces a different type of invasion. Thousands of migrants, most from North Africa and the Middle East, are storming an ineffective "barricade" in Calais, France, as they attempt to enter England via the Chunnel, a 30-mile rail tunnel linking Folkestone, Kent, with Coquelles, Pas-de-Calais, in northern France.