Neelakanta Swamy temple is located to the east of Padmanabhapuram palace in Kanyakumari district.
Nestled at the foot of the majestic Veli hill, the historic Padmanabhapuram palace complex is an architectural marvel. The grand complex, consisting of several palaces, treasury, offices, temples, ponds, and guest houses, was converted into a museum in 1935.
Enclosed within the fort walls is a remarkable settlement, its pattern clearly defined by the caste-based social hierarchy of yesterday. The houses of the nobles and important officials, once associated with the royals, is seen strewn about the palace complex. Surprisingly, the core of this settlement is not the sprawling palace complex, but a temple!
The architectural style is undeniably Dravidian, the lofty gopuram and the beautifully carved stone pillars bear testimony to the skill of the master craftsmen associated with its construction. Even though the exact date of its origin remains elusive, the temple and its legends make the warp and weft of local legends. The temple houses several inscriptions dating from the thirteenth century, perhaps a clue to its antiquated heritage. While the oldest inscriptions found in the temple date back to the early thirteenth century, the latter ones could be dated to the early twentieth century. One such inscription can be seen in the Western side of the temple tank. The inscription from 1907 A.D. records the name of Dewan Peishkar Narayana Iyen Subramanya Iyen and the then ruler.
The temple, as the name indicates, is dedicated to Lord Siva. However, one can find alongside the main shrine, another shrine housing Anandavalli Devi, the idol bearing close resemblance to the one seen in the famed Madurai Meenakshi temple.
An important destination in the Sivalaya Ottam (ritual marathon undertaken on Sivarathri when devotees visit 12 Siva temples), Neelakanta Swamy temple and its charming rural setting comes to life during Navarathri and the annual festival conducted in the Tamil month of Panguni (March-April).
Source : Finding temple