Castell Aberlleiniog is built in a strategic position beside the
Menai Strait opposite the Norman castle at
Abergwyngregyn, showing that visual communication was important to the Norman invaders. It was probably erected by Hugh d'Avranches, 1st Earl of Chester, when he conquered Gwynedd in 1088. There are few historical documents that detail the events the castle has seen through its life, however some do survive, including a record of a siege in 1094 by
Gruffudd ap Cynan on his return from Ireland. The siege was successful, 124
Norman defenders died in the battle. Gruffudd was later successful in driving Hugh out, and after this, Anglesey remained under the control of the Welsh until the arrival of
Edward I two hundred years later. It is not known whether they made use of Castell Aberlleiniog. The original Norman timber structure is long gone, replaced by a stone structure at some point prior to the mid-17th century, when it was destroyed by Thomas Cheadle, the constable of
Beaumaris. The site was restored from 2008 and is (2016) open to the public. The keep had broad ramparts fronted by a narrow wall rising to a parapet; each corner contained a round tower, the remains of which can still be seen. ==See also==