Bloody Tube July 7, 2005 - London, England - The walking wounded leave Russell Square tube station after a series of four coordinated bombings in London's transport system wounded 700 and killed at least 56 people, including the four suspected bombers. A group called the Secret Group of al Qaeda's Jihad in Europe unofficially claimed responsibility for the incident on the Internet.

This was the deadliest single act of terrorism in the United Kingdom since 270 died in the 1988 bombing of Pan Am Flight 103, and it's the deadliest bombing in London since World War II.

London has a long history of terror. The city survived many devastating bombings in the 20th century, among them, the German Blitz of WWII, which remains an important symbolic part of the city's history and character. During the Blitz, city residents frequently took shelter in the London Underground. Some, who were tired of the constant evacuations, moved into the tube stations, where as many as 177,000 people took shelter.

On Sept. 8, 1973, the IRA bombed London's Victoria Station. Two days later, bombs exploded at two Underground stations in Central London, injuring 21 people. Forty-eight hours later, more blasts rocked London's Oxford Street and Sloane Square. The IRA claimed responsibility for all of the attacks. Picture (c) TERRY BRADFORD/Daily Mail/ZUMA Press