Gwerclas usually refers to a former castle and farmstead close to
Cymmer in the parish of
Llangar in the ancient
cantref of
Edeyrnion,
Wales. It is now just an uninhabited upland area. The modest castle found at the site during the early
Middle Ages is now completely ruinous. The ancient Barons of
Cymmer yn Edeyrnion (known as the
Hughes of Gwerclas) cite this place as their ancestral home. Prior to the resettling of the castle in 1186 by the ancestors of the Hughes family it was the power base of the mysterious
Maer Du or "Black Mayors" of Edeyrnion.