Madoc is a township in Hastings County in Eastern Ontario, Canada. The township was named after Welsh prince Madoc ap Owain Gwynedd, credited by some with discovering North America in 1170. There exists an alternative explanation, for which no evidence exists, that the name comes from a small Welsh village, Llanmadoc, on the Gower Peninsula of Wales, not far from the city of Swansea. Its post office dates from 1836.