Gurudwara Manji Sahib is Ambala's most important Sikh shrine, standing close to the Grand Trunk Road in the old city. It is associated with Guru Hargobind, who is said to have stayed here, and with Guru Gobind Singh, whose childhood travels also connect to the site.
The building is active and devotional, not a museum piece. Come with covered head and bare feet, take time around the sarovar and baoli, and use the visit as a way into Ambala's older religious geography before heading to the cantonment side.