The fort is situated on the Thiruvananthapuram-Nagercoil National highway at Puliyoorkurichi.The fort was the most important military barracks of the Travancore rulers, when Padmanabhapuram was their capital.The fort was rebuilt during the reign of Marthanda Varma, Venad King, during 1741-44 under the supervision of Eustachius De Lannoy, a Flemish naval commander of the Dutch East India Company, who later served as the Chief of the Travancore Army.The fort is built of massive granite blocks around an isolated hillock.The tombs of the Dutch Admiral Eustachius De Lannoy, (in whose honour the fort was once called Dillanai Kottai— De Lennoy's Fort), and of his wife and son can still be found inside a partly ruined chapel in the fort. De Lannoy's body was buried within the fort and a chapel was built at his burial site . De Lannoy's tombstone lies within the walls of the ruined chapel. The inscriptions on his stone are both in Tamil and in Latin. His wife and son were buried by his side.