Alagankulam is a village situated on the east coast in the Ramanathapuram Taluk and district. The village is situated on the banks of the Vaigai River and is about 3 kilometres (1.9 mi) away from the seashore. The village is located 18 kilometres (11 mi) east of Ramanathapuram. The village has a population of 15,473 as of the Population Census of 2011.