The Kymin, (Welsh: Cae-y-Maen), is a hill overlooking Monmouth, in Monmouthshire, Wales. It is located approximately one mile east of Monmouth, on the eastern side of the River Wye and adjacent to the border with the Forest of Dean and England. The summit of the hill, about 800 feet above sea level, is known for its neo-classical monuments, the Roundhouse and the Naval Temple, built between 1794 and 1800.