Bollywood superstar Aamir Khan turned `Banarasi Babu` to promote `3 Idiots` as he made his first stop in the holy city.

The 44-year-old actor has put on a disappearing act and is on a seven city tour to promote the film.

Aamir reached Varanasi on Friday and traveled through the narrow lanes of the old city to search his mother, Zeenat`s birth place in Teliyanala area, near the Prahlad Ghat at the banks of river Ganga.

Wearing a simple shirt, his face covered with a muffler, Aamir hid himself in old sunglasses. He stayed in the city for three days in the disguise of an old man.

The morning before leaving the city, Aamir reached the Teliyanala mohalla in the Kotwali area to visit his mother`s birthplace Khwaja Manzil, which is in a dilapidated condition.

Aamir also visited the famous Dasaswamedh Ghat.

The actor has roped in `Master Blaster` Sachin Tendulkar to endorse the movie, who gave the first clue about his whereabouts.

“I don`t know anything more than this,” Sachin had said as he read out the clue in Hindi, “Kahan jaoon kaise jaoon, itne sawal kaise suljaoon, kabhi to sochoon main udd jaoon. Kabhi sadak pe car bhagaoon, ya chuk chuk gaadi ko aazmaoon, chahe main jaise bhi jaoon, maa ke aangan mein raat bitaoon.”

Sachin has already watched the film at Ketnav studios in suburban Bandra along with his wife Anjali and friends including cricketer Ajit Agarkar.

`3 Idiots`, releasing on December 25, has Aamir playing a 22-year-old engineering student along with actors Madhavan and Sharman Joshi. Kareena Kapoor is the female lead.