|Motto: Tra môr, tra Meirion
(While the sea lasts, so shall Meirionnydd)
Ancient extent of Merionethshire
|1831 area||385,291 acres (1,559.22 km2)|
|1911/1961 area||422,372 acres (1,709.28 km2)|
- 1831 density
- 1911 density
- 1961 density
|Governance||Merionethshire County Council (1889-1974)|
Coat of arms of Merionethshire County Council
The spelling of the Welsh name in standard modern orthography is Meirionnydd (for the geographical area) or Sir Feirionnydd (for the county), with a double <nn>, but the variant with a single <n> is sometimes found in older works.
Merionethshire is a maritime county, bounded to the north by Caernarfonshire, to the east by Denbighshire, to the south by Montgomeryshire and Cardiganshire, and to the west by Cardigan Bay. With a total area of 1,731 km², it is one of the more sparsely populated counties in Great Britain.
The Merioneth area remains one of the strongest Welsh-speaking parts of Wales. The coastline consists alternately of cliffs and stretches of sand and the area generally is the most mountainous in Wales; a large part of the Snowdonia National Park lies within it. The greatest heights are Aran Fawddwy 905 m (2,970 ft) and Cadair Idris 893 m (2,929 ft). The chief rivers are the Dwyryd, the Mawddach and the Dyfi. Waterfalls and small lakes are numerous, the largest being Bala Lake (4 miles long and 1-mile (1.6 km) broad).
Merioneth was an important part of the Welsh slate industry in the nineteenth and twentieth centuries, with major quarrying centres at Blaenau Ffestiniog in the north of the county and Corris in the south.
An administrative county of Merioneth was created under the Local Government Act 1888 on 1 April 1889 and abolished under the Local Government Act 1972 on 1 April 1974. The bulk formed the Meirionnydd district of Gwynedd, with a small area in the north east, Edeirnion Rural District, becoming part of the Glyndŵr district of Clwyd.
As a result of the Local Government (Wales) Act 1994, which came into force on 1 April 1996, the Glyndŵr area was made a part of the new Denbighshire principal area, with the rest forming a new Caernarfonshire and Merionethshire principal area. The latter area was, however, renamed Gwynedd almost immediately.
Main towns 
The main towns are
- Dolgellau (former county town, and administrative centre)
- Blaenau Ffestiniog
The main industries today are agriculture, forestry and tourism.
Places of special interest (with grid reference) 
- Cadair Idris (SH711130)
- Castell y Bere (SH667085)
- Cymer Abbey (SH721195)
- Harlech Castle (SH5731)
- Portmeirion Italianate village (SH589372)
- Rhug Chapel (SJ063439)
- Tomen-y-mur Roman Fort (SH7038)
- Ffestiniog Railway (SH6946)
- Corris Railway (SH7507)
- Talyllyn Railway (SH5800)
- Fairbourne Railway (SH6112)
See also 
- List of Lord Lieutenants of Merioneth
- List of Custodes Rotulorum of Merioneth
- List of High Sheriffs of Merioneth
- List of MPs for Merioneth
- Vision of Britain - 1831 Census
- Double 'nn' is found in the title of a number of Welsh-language books, e.g. Crwydro Meirionnydd, a companion to the area by T. I. Ellis (Llandybie, 1954), and the county atlas published by the old county council (Atlas Merionnydd, Y Bala, 1972).
- For the single 'n' variant see, for example, Melville Richards, Welsh Administrative and Territorial Units. University of Wales Press, Cardiff 1969.
- "The County of Gwynedd (Electoral Changes) Order 2002, Welsh Statutory Instrument 2002 No. 3274 (W.312)". Office of Public Sector Information. 2002. Retrieved 2008-07-27.