Karthikai Deepam or Karthikai vilakkidu is a Hindu specially Tamils Festival of Lights. The festival is observed in most Hindu homes and every temple, and falls in the month of Karttikai (mid-November to mid-December) as per Tamil calendar

Karthigai festival in Tiruvannamalai is very famous. On Karthigai day, a huge fire lamp is lit up on the hill, visible for several kilometers around. The fire (deepam) is called Mahadeepam. Hindu devotees visit the place, to pray and make offerings to lord Shiva.

Lamps lit with oil are a symbol of holiness in Indian culture. Karthigai Deepam is no exception. Beautifully lit lamps are found all around the home to bring in happiness to the home. This festival occurs when the moon is seen fully in the sky. Karthigai Deepam is celebrated during Purnima or full moon day when the moon is in line with the six star constellation called Karthigai. Tamil Nadu celebrates this occasion in November and December months for 10 days. All the people make merry, wear new clothes and rejoice with happiness. They exchange gifts and try to meet all their relatives during the festival.

According to the Tamil belief, if a person takes birth in Tiruvarur and dies in Varanasi or Chidambaam, his life is fulfilled to the utmost level. People believe that Lord Shiva appeared in Thiruvannamalai hills on this day and the people like to commemorate the situation by lighting a huge fire on the top of the hill. Ghee and camphor are used to light the huge fire to set up connection to God directly. The place looks fabulous and people shout saying Annamalaiyarku Arohara. Most people find the pleasure to watch this happening with own eyes by standing near the fire. The occasion is marked by a fair occurring in the area. People love to visit the fair and buy everything that is sold there. Cattle are also sold at the fair

The deities are placed on the vehicle and carried along the roads like procession for the people to have a look. The vehicles are magnificently decorated to make them fill happy and interested. The lighting of the flame on the hill starts mostly at 5 pm in the evening. No one wants to miss the auspicious occasion and rush out of their homes to be present there.

Women try to make their homes look welcoming and fresh during this time. They wear new clothes and tidy up their homes to invite their brothers. The home looks heavenly with oil lit lamps everywhere. Children blow crackers and make merry with friends and family. This is like a family get-together. Indians want to be preset in their homes during this wonderful festival. They try to return to India from anywhere in the world to meet their parents, sisters and relatives.

Karthigai Deepam is a fantastic festival of Tamil Nadu which the Tamils never want to miss out. They wait a year around to enjoy during this time. They have the mouth watering food in homes and go out to see the decorations in the streets and the homes of the relatives. Festival time is really great when people forget all their worries and come together to spend some quality time. They take holidays from offices and forget about the daily tension in life. They pray to God and become closer to God during such festivals