James Fort (Irish: Dún Rí Shéamuis) is an early 17th century pentagonal fort located on Castlepark peninsula in Kinsale harbour. Situated downstream from Kinsale on the River Bandon, the fort was built to defend the harbour and seaborne approaches of the town. Following the construction of Charles Fort on the opposite side of the harbour in the late 17th century, James Fort became known as the "old fort" (Irish: an Seandaingean).