Ynys Castell from the Beaumaris road

Ynys Castell (grid reference SH564727) is a small island in the Menai Strait which separates Anglesey and mainland Wales. It is an extruding piece of Precambrian schist lying to one side of the Afon Cadnant estuary. It lies between Ynys y Bîg and Ynys Gaint. There are many places named Beaumaris: Beaumaris, Anglesey in Wales, for which the other places are named Beaumaris, suburb of Melbourne, Victoria (Australia), Australia Beaumaris, Tasmania, Australia This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... The British national grid reference system is a system of geographic grid references commonly used in Great Britain, different from using latitude or longitude. ... The Menai Strait (in Welsh Afon Menai, the River Menai) is a narrow stretch of shallow tidal water about 14 miles (23 km) long, which separates the island of Anglesey from the mainland of Wales. ... Anglesey (Welsh: , pronounced (IPA)), is an island and county at the northwestern extremity of Wales. ... Motto: (Welsh for Wales forever) Anthem: Hen Wlad Fy Nhadau Capital Cardiff Largest city Cardiff Official language(s) Welsh, English Government Constitutional monarchy  - Queen Queen Elizabeth II  - Prime Minister of the UK Tony Blair MP  - First Minister Rhodri Morgan AM Unification    - by Gruffudd ap Llywelyn 1056  Area    - Total 20,779... The Precambrian is an informal name for the eons of the geologic timescale that came before the current Phanerozoic eon. ... Schist The schists form a group of medium-grade metamorphic rocks, chiefly notable for the preponderance of lamellar minerals such as micas, chlorite, talc, hornblende, graphite, and others. ... Clapper bridge over Afon Cadnant The Afon Cadnant is a small river draining to the Menai Strait about 1 km north-east of the Menai suspension bridge, North Wales. ...