Hari Utthapana Ekadashi
This festival occurs on the 11th day of the bright fortnight (Sukla Paksha) of Kartika when the deities finally wake up from their sleep of four months (the Chaturmasya of rains).
References:
- http://magazines.odisha.gov.in/Orissareview/2016/July/engpdf/83-85.pdf