A realm below the earth
Sanskrit sutala; the texts we read do not explain the name. It is one of the seven patalas, the lower realms.
A lower realm of the Puranas where, in the Bhagavata, Vishnu sends King Bali and promises to guard him. Kerala tradition names the netherworld more often as Patala.
Kerala's grandest festival marks the yearly homecoming of King Mahabali, the generous asura ruler whom Vishnu as Vamana sent below, yet let return each year.
Vamana's three paces and King Bali's kept promise as the Bhagavata Purana tells it, and how Kerala's Onam tradition tells Mahabali's yearly return.
The glorious story from the Brahma Vaivarta Purana of Lord Vishnu turning onto His side in Yoga Nidra and the advent of Vamana Avatar liberating King Bali in Bhadrapada Shukla Paksha.