Nallur Kandaswamy Kovil is a significant Hindu temple, located in Nallur, Northern Province, Sri Lanka. The presiding deity is Lord Murugan or Katharagama Deviyo in the form of the holy 'Vel' in the Sanctum, the primary shrine, and in other forms, namely, Shanmugar, Muthukumaraswami, Valli Kaanthar with consorts Valli and Deivayanai, and Thandayuthapani, sans consorts in secondary shrines in the temple. Origins – The earlier shrines of Kandaswamy in Nallur The original, Kandaswamy Temple was founded in 948 ad. According to the Yalpana Vaipava Malai, the temple was developed at the site in the 13th century by Buwanika Bahu, a minister to the King of Kotte. Sapumal Kumaraya (also known as Chempaha Perumal in Tamil), who ruled the Jaffna kingdom on behalf of the Kotte kingdom is credited with building the third Nallur Kandaswamy temple. 

Nallur served as the capital of the Jaffna kings, with the royal palace situated very close to the temple. Nallur was built with four entrances with gates. There were two main roadways and four temples at the four gateways. The present rebuilt temple that exist now do not match their original locations which instead are occupied by churches erected by the Portuguese. The center of the city was Muthirai Santhai (market place) and was surrounded by a square fortification around it. There were courtly buildings for the kings, Brahmin priests, soldiers and other service providers. The old Kandaswamy temple functioned as a defensive fort with high walls. In general, the city was laid out like the traditional temple town according to Hindu traditions.

Wikipedia