Firth of Clyde

Firth of Clyde
Clyde Waters, Clyde Sea
Map of the Firth of Clyde.
Firth of Clyde Location within Argyll and Bute Firth of Clyde Location within Scotland
Location	Scotland
Coordinates	grid reference NS153652
Type	Firth
Etymology	Scottish
Part of	Irish Sea
River sources	River Clyde
Basin countries	Scotland
Surface area	4,279 km2 (1,652 sq mi)
Average depth	58 m (190 ft)
Max. depth	198 m (650 ft)
Shore length1	1,256 km (780 mi)
Surface elevation	0 m (0 ft)
Frozen	No
Islands	Isle of Arran, Isle of Bute, Isle of Cumbrae
References
Ramsar Wetland
Designated	5 September 2000
Reference no.	1036
1 Shore length is not a well-defined measure.

The Firth of Clyde is the estuary of the River Clyde, on the west coast of Scotland. The Firth has some of the deepest coastal waters of the British Isles and is sheltered from the Atlantic Ocean by the Kintyre Peninsula. The Firth lies between West Dunbartonshire in the north, Argyll and Bute in the west, and Inverclyde, North Ayrshire and South Ayrshire in the east. Kilbrannan Sound is a large arm of the Firth, separating the Kintyre Peninsula from the Isle of Arran. The Kyles of Bute separates the Isle of Bute from the Cowal Peninsula. The Sound of Bute separates the islands of Bute and Arran.

The Highland Boundary Fault crosses the Firth. The Firth also played a vital military role during World War II.

The Firth is sometimes called the Clyde Waters or Clyde Sea. It is customarily considered to be part of the Irish Sea.