Ersil is a village in Taşköprü District, in Kastamonu Province, Türkiye. Ersil lies at 663 m above sea level, in the Ilgaz mountains. It has 488 inhabitants. The nearest city is Kastamonu, 22 km to the west. Among the landmarks around are Mahmut Bey Mosque (29 km), Pompeiopolis (18.4 km) and Nasrullah Mosque (22 km).