Place to visit during Chaturmas | pilgrimage during chaturmasam

Source: Skanda purana translation

Best place to stay during Chaturmas is Puri. This place has been give the name of god itself -  Purushottama kshetram.

God goes to sleep during chaturmasya. But he stays in this place visibly like staying in vaikuntam.
By staying in puri, one gets the merits of staying in every holy place each of the days.

Seeing the lord at this place on one of the days of chaturmas, is equal to seeing god on all days in eight months.
A sinful man, if stays in Puri for one set of chaturmas, he dispels all the sins.

Procedure to start the festival of lord going to sleep is detailed in Skanda purana part 5.

In Puri jagannath temple, they give a prasadam called nirmalya.. It is the Cooked rice after neivedyam, It is considered very holy. It is considered that god himself eats the food and remaining food is called nirmalya. I

If a person consumed this mahaprasadam, it is considered to remove all sins.
Nirmalya is considered very pure and does not get defiled with anyone's touch. 

Even if it is dried it is considered holy, It can be eaten as it is. As soon as it is received, it should be eaten, even if the person is in fasting.. even when bodily impure.

As per skanda purana, Generaly god sees food in all holy places.. it is only at this place that god eats the food offered.