By pure coincidence, I arrived in India at the same time this festival was happening. Kanwar Yatra is an annual pilgrimage of worshippers of Shiva carry holy water from the Ganges to certain holy places in India. The water is carried via the contraption (also called a kanwar) similar to the one the man is holding in the cover photo. Roads that the pilgrims travel on (in particular the Delhi-Haridwar national highway) are often closed to cars, so traffic becomes super congested.
Many I saw travelled on foot, but some took scooters too. People along the way set up camps for the pilgrims to stay the night and to feed them.
At night there are huge parties dedicated to Shiva, with giant trucks playing music on giant speakers with lights shining everywhere. The festival lasts for five days with the streets blocked and the parties happening for every single day.