Panguni is the last month of the year as per tamil calendar. The specialty of Panguni Uthiram is the coming together of the full moon day and the Uthira Nakshatra thereby setting phase for the various fervent celebrations. Panguni Uthiram has a very special importance for the Hindus. The chief highlight of the day is the celebrations that happen in the Muruga temples (Lord Subramanya).
Most interestingly several celestial weddings or divine marriages of gods is said to have taken place on the day of Panguni Uthiram. Notably, the Puranas talk about the marriages of shiva and Parvati, Murugan and Devayani, Andal and Ranganatha, and Rama and Sita took place on this holy day. There are also other important happenings ascribed to this day including the incarnation of Lord ayyappa and the incarnation of Goddess Mahalakshmi. Therefore this day has a great significance.
On the day of Panguni Uthiram, thousands of devotees throng at the six famed temples of Muruga in tamilnadu called as Arupadai Veedu. There are elaborate events organized in these temples. Devotees walk over several miles on foot as a mark of their devotion to Lord Muruga with many of them seen carrying milk pots and a set up called Kavadi on their shoulders and heads carrying some objects to be offered at the temple.