New Delhi, May 27 -- The Archaeological Survey of India (ASI) has begun a survey of Tirupparankundram Hill - a 172.70-acre protected hillock - on the outskirts of Madurai, following directions from the Madras high court. The survey, being jointly held by officials of ASI and revenue department, began under tight police security on Monday. The three-day survey is using the Differential Global Positioning System (DGPS) technology for high-precision boundary mapping, recording every structure and boundary marker to centimetre-level accuracy. "Following the directions of the Madurai bench of the Madras High Court, the ASI team, along with revenue officials, has commenced the scientific survey and measurement of the Thiruparankundram hill. Moder...