Arunachala is a sacred mountain located in the Indian state of Tamil Nadu. It is considered a spiritual center and is revered by many followers of Hinduism. The mountain is associated with the deity Shiva and is believed to be a manifestation of the divine. Pilgrims and spiritual seekers visit Arunachala to meditate and seek enlightenment. The town of Tiruvannamalai lies at the base of Arunachala and hosts several ancient temples, including the famous Annamalaiyar Temple. The annual festival of Karthigai Deepam attracts thousands of devotees who gather to witness the lighting of a massive beacon on the mountain's summit, symbolizing spiritual illumination.