Bhai Bulaki Das Masand and Raja Ram Rai came to Patna Sahib to escort Guru Ji to Dhaka and Kam-Roop Desh. Mata Nanaki Ji wanted that Guru Ji might stay in Patna Sahib for some more time. But Guru Ji started His journey due to wishes and love of Sikh Sangat. Guru Tegh Bahadur Sahib' family and His brother-in-law Kirpal Chand Ji stayed in Salas Rai Johri's home, which was later converted into Gurdwara Patna Sahib.
It was the time when people were terrorised because of orders of Aurangzeb against Hindu temples. Guru Ji started visiting village-to-village and door-to-door to encourage people to be fearless for four long years.
Traveling through Mungher, Bhagalpur, Kala Gau, Sahib Ganj, Kant Nagar, Raj Nagar and Malda cities, Guru Ji reached Dhaka. Kings, ministers and masands of that time welcomed Guru Ji.
Aurangzeb had sent Mirza Raja Jai Singh’s son Raja Ram Singh against North Asam’s Ahomi king Chakardhwaj. Sri Guru Tegh Bahadur Sahib was in Assam those days. He instrumented compromise between two sides and hence saved poor people from bloodshed in 1670 AD. Raja Ram Singh never forgot that assistance and was always grateful to Guru Ji.
Guru Gobind Singh Ji was born in Patna Sahib on December 22, 1666 AD (Poh Sudi Satvin 1723). Bhai Dayal Das Ji soon reached Dhaka to give this good news to Guru Tegh Bahadur Ji. Guru Tegh Bahadu Ji was coming to Patna Sahib traveling through Silhat Chita Gau and Dhobri etc places. News of His arrival filled the hearts of Sangat of Patna Sahib with happiness. Mata Nanaki Ji, Mata Gujari Ji and Balak Gobind Rai Ji were extremely happy.
Gur Teg Bahadar Ji seated in a garden of a navab outside the city of Patna. This garden is now known as Gurdwara Guru Ka Bag. It was a good day of Vaisakh Sudi Satvin. Sangat took Balak Gobind Rai in a palanquin (paalki) to the garden to get the holy glimpse of the Ninth Guru. On one side Father Guru climbed down the horse on the other side the Son came out of paalki. The Latter touched the feet of His father. Father took His son and kissed His face. Sangat touched feet of the ninth Guru and attained high spirits. Gurdwara Guru Ka Bagh is the souvenir of first ever meet of Father and Son.
Well at Gurdwara Guru Ka Bag known as Guru Ji da Khuh
A branch of imli tree under which Guru Teg Bahadur Sahib sat at
Gurdwara Guru Ka Bag in 1673 AD.
People plant saplings in the Gurudwara when their wishes are fulfilled. Good wishes are fulfilled and naam daan ishnana are bestowed upon here. A mela is organised here on Satvin of every month. Couples are blessed with issues on taking bath with holy water of the well. Annual mela is organised on vaisakh sudi satvin.
This garden belonged to Karim Bakhash and Rahim Bakhash. It was dry of quite some time. It became green when Guru Ji’s charans touched it.
— Parbandhak Committee
History written above is translated from this history board in Punjabi placed in the Gurudwara. Click the image to see its large view.