The Nagarcoil Forward Defence Line was an Army Forward Defence Line (FDL) that separated Sri Lankan Army and LTTE militia in Northeastern Kilinochchi - Southeastern Jaffna border.
The FDL comprised a very narrow isthmus connecting Jaffna peninsula to rest of Sri Lanka.
It is only a few hundred meters wide and on the both sides heavily fortified and mined as well as abundant in booby traps.
Compared to Muhamalai FDL, the Nagar Kovil FDL was much narrower and so it was extremely difficult to overrun enemy bunker lines.
For the past several years, along with the Muhamalai FDL, Nagarcoil FDL was the most active front in the Sri Lankan Civil War.