People of Kerala celebrate Onam every year. The Onam festival is the most important festival of Kerala. Onam is an harvest festival that is celebrated by all people in Kerala. The festival of Onam usually falls in August - September months. The festival of Onam last for 10 days starting with Atham. Onam festival have a story connected with it that says the festival is celebrated to remember King Mahabali who once ruled Kerala. It is believed that on the day of Thiruvonam, King Mahabali visits Kerala.