Five men today denied plotting to kill and cause explosions on London's transport system on 21 July last year.
The men also denied various charges of possessing "an improvised explosive device" and four denied attempted murder.
Their trial is due to take place on 3 October this year.
A sixth man, Adel Yahya, 23, from London, was remanded to another hearing in June. He was charged with conspiracy to cause explosions likely to endanger life but did not enter a plea.
Muktar Said Ibrahim, 27, Ramzi Mohammed, 23, Yassin Omar, 24, Manfo Asiedu, 32 and Hussain Osman, 27, all from London, entered pleas before the trial judge, Mr Justice Fulford, at The Old Bailey.
All denied two charges of conspiracy to murder and conspiracy to cause explosions likely to endanger life between 1 January and 30 July last year.
They all pleaded not guilty to individual charges of having an improvised explosive device with intent to cause an explosion likely to endanger life on 21 July last year.
Osman, Omar and Mohammed pleaded not guilty to the attempted murder of passengers on the Transport for London system.
Ibrahim pleaded not guilty to the attempted murder of passengers on a number 26 London bus.
The men were arrested after bombs in rucksacks failed to go off at London Underground stations and a bus on 21 July. Another device was found in bushes near Wormwood Scrubs, west London.
The men appeared in court by video link from Belmarsh Prison. Osman appeared on video link from Woodhill Prison.
Ibrahim, of Stoke Newington, Mohammed, of North Kensington, Omar, of New Southgate, Asiedu, of Finsbury Park, Osman, of Stockwell and Yahya, of Tottenham, were all remanded in custody.
They spoke only to confirm their names during the 90-minute hearing.
Osman's wife, Yeshiemebet Girma, 29, her sister Muluemebet Girma, 21, and their brother Essayas Girma, 20, all from Stockwell, were later remanded to June in a separate hearing.
Also remanded during the same hearing were Shadi Abdelgadir, 22, Omar Almoghoul, 20, and Mohammed Kabashi, 23, all from Brighton.
All but Yeshiemebet and Kabashi - who appeared by video link from prison - were on bail.
They were accused of assisting an offender, Osman, and failing to disclose information on terrorism. They face trial on 5 February next year.Reuse content