2005 Attack Shaped Security Planning for Olympics

LONDON - To understand the gargantuan security operation that authorities have prepared for the Olympic Games that open here Friday - nearly twice as many military troops are on the streets here as Britain has deployed in Afghanistan, for starters - it helps to remember what happened the morning after London won the right to host these games seven years ago.

On July 7, 2005, homegrown militants detonated bombs in the city's Underground subway and on a passenger bus, killing dozens in one of the worst terrorist attacks in the country's history.

Photo credit Wikipedia: Headlines London bombing 7 july 2005 Waterloo station