Singh arrived in a special aircraft which landed at 1150 hrs at Sanganer airport where Rajasthan Chief Minister Ashok Gehlot, Governor Margaret Alva and others welcomed him.
From the airport, the Prime Minister headed to Raj Bhawan for a brief halt, before reaching the Chintan Shivir venue at Birla auditorium.
The two-day Chintan Shivir is beginning today and will be followed by AICC meeting on Sunday.
UPA Chairperson Sonia Gandhi and AICC General Secretary Rahul Gandhi would arrive here around 2 PM.
Most of the delegates including chief ministers, union ministers, party leaders, NSUI and Youth Congress leaders have reached here to brainstorm on political, socio-economic and global issues and challenges.
The session, to be attended by 347 delegates, would formally begin with opening remarks by Sonia Gandhi.
Meanwhile, a few hoardings and billboards put up at different places to welcome the PM and UPA Chairperson were displaced by rain and winds last night, and were replaced in the morning by party workers.