Danda (alias Dandaka, a kingdom and a forest had the same name) is a frequently featured region in Hindu mythology. It was a colonial state of Lanka under the reign of Ravana. Ravana's governor Khara ruled this province. It was the stronghold of all the Rakshasa tribes living in the Dandaka Forest. It is roughly the Nashik District, Maharashtra with Janasthana (Nashik city) as its capital. It was from here that the Rakshasa Khara attacked Raghava Rama of Kosala, who lived with his wife and brother at Panchavati (modern day Nashik), not far away.
References
Danda Kingdom Wikipedia(Text) CC BY-SA