The 7 July 2005 London bombings, also referred to as 7/7, were a series of four coordinated suicide attacks carried out by Islamist terrorists that targeted commuters traveling on London's public transport during the morning rush hour.

Three terrorists separately detonated three homemade bombs in quick succession aboard London Underground trains in Inner London. Later, a fourth terrorist detonated another bomb on a double-decker bus in Tavistock Square. The train bombings occurred on the Circle Line near Aldgate and at Edgware Road, and on the Piccadilly Line near Russell Square.

Apart from the bombers, 52 people of 18 different nationalities were killed and nearly 800 were injured in the attacks. It was the UK's deadliest terrorist incident since the 1988 bombing of Pan Am Flight 103 near Lockerbie, and the UK's first Islamist suicide attack.

The explosions were caused by improvised explosive devices made from concentrated hydrogen peroxide and pepper, packed into backpacks.