This Gurdwara is one of the most important historical Gurdwaras having a history of martyrdom. It is located at Chandni Chowk area in Old Delhi. At this historic site the ninth Sikh Guru, Guru Teg Bahadur was beheaded in the year 1675 on the orders from Mughal emperor Aurangzeb for refusing to convert to Islam. According to the historical story when Guru Tegh Bahadur died there was no one to even pick up the corpse. The rains came down suddenly. Two of his disciples took his body and head and performed the final rituals. The present Gurudwara structure was built in year 1930.The main structure is a huge and very spacious open hall.
The Guru Granth Sahib covered with a big red tunic cloth and heaps of garlands is kept under a bronze canopy in the middle of the room.
One can also find the banyan tree where the noble Guru was martyred. There is also an enclosed structure within the gurudwara where the Guru was kept as a prisoner before he was finally executed.
http://en.wikipedia.org/wiki/Gurudwara_Sis_Ganj_Sahib
http://www.sikhiwiki.org/index.php/Gurdwara_Sis_Ganj_Sahib