Worship of Jagannatha is the worship of the creator and sustainer who immediately preserves the human who chants his name by removing her or his sins. The faithful is emancipated from all her or his earthly bindings of evil and ready to meet the Ultimate in the next world.
Religious festivals associate with the deity
The Ratha Yatra or the Car Festival is the most famous festival associated with Lord Jagannatha all over the country but especially Puri Temple that is the primary dwelling place. The Lord goes for a change of air for a fortnight after which during Ulta Ratha or return festival, he returns to the Temple.
Region where deity is worshipped most
The primary festival of the Lord is of course conducted in Puri, Orissa, but the festival is celebrated with much fervor all over Eastern India. Large chariots are brought out on the city streets with the deities that is followed with much devotion. Kolkata, Mayapur and several other places where the ISKON have Temples celebrate the festival with much fanfare.