The Flow Country is the largest blanket bog in Europe, and covers a large inland area in the west of the county.

From the 9th century the Caithness area was ruled by the Jarl of Orkney, who at different times owed allegiance to both Norway and Scotland.

A shire called Caithness covering the same area as the earldom was created in 1641, after a couple of earlier abortive attempts.

Until the latter part of the 20th century when large areas were planted in conifers, this level profile was rendered still more striking by the almost total absence of woodland.

The county is fringed to the north and east by dramatic coastal scenery and is home to large, internationally important colonies of seabirds.

The surrounding waters of the Pentland Firth and the North Sea hold a great diversity of marine life.

This consists of the cemented sediments of Lake Orcadie, which is believed to have stretched from Shetland to Grampian during the Devonian period, about 370 million years ago.

Because of the ease with which the sandstone splits to form large flat slabs (flagstone) it is an especially useful building material, and has been used as such since Neolithic times.

Caithness is one of the Watsonian vice-counties, subdivisions of Britain and Ireland which are used largely for the purposes of biological recording and other scientific data-gathering.

The underlying geology, harsh climate, and long history of human occupation have shaped the natural heritage of Caithness.

Both grey and common seals come close to the shore to feed, rest, and raise their pups; a significant population over-winters on small islands in the Thurso river only a short walk from the town centre.

Around 1,500 km2 (580 sq mi) of the Flow Country is protected as both a Special Protection Area (SPA) and Special Area of Conservation (SAC) under the name Caithness and Sutherland Peatlands,[4][5] and a portion is further designated as the Forsinard Flows national nature reserve.

These include the Grey Cairns of Camster, the Stone Lud, the Hill O Many Stanes, a complex of sites around Loch of Yarrows near Thrumster, and over 100 brochs.

[13] When the Norsemen arrived, probably in the 10th century, the county was inhabited by the Picts,[14] but with its culture subject to some Goidelic influence from the Celtic Church.

The bishop's seat was initially at Halkirk, but in the early 13th century was moved to Dornoch Cathedral (now in Sutherland), which was begun in 1224.

In 1667 Commissioners of Supply were established for each shire, which would serve as the main administrative body for the area until the creation of county councils in 1890.

Although they shared a sheriff after 1748, Caithness and Sutherland remained legally separate counties, having their own commissioners of supply and, from 1794, their own lord lieutenants.

[34] Although Wick had been declared the head burgh of the shire in 1641, for much of the next 200 years the sheriff held most courts and had his clerk's offices in Thurso.

[35][36] Elected county councils were established in 1890 under the Local Government (Scotland) Act 1889, taking most of the functions of the commissioners of supply (which were eventually abolished in 1930).

These include Castletown, Dunbeath, Dunnet, Halkirk, John o' Groats, Keiss, Lybster, Reay/New Reay, Scrabster and Watten.

Other, smaller settlements include: Caithness is served by the Far North railway line, which runs west–east across the middle of the county serving Altnabreac and Scotscalder before splitting in two at Georgemas Junction, from where the east branch continues to Wick whilst the north branch terminates at Thurso.

The Norn language was introduced to Caithness, Orkney, and Shetland by the Norse occupation, which is generally proposed to be c. AD 800.

It is sometimes erroneously claimed that Gaelic has never been spoken in Caithness, but this is a result of language shift to Scots,[66][67][68][69][70][71] and then towards Standard Scottish English during recent centuries.

Gaelic speakers seem to first figure in the early stage of the Scandinavian colonisation of Caithness, gradually increasing in numerical significance from the 12th century onwards.

[74] The emergent Northern Scots dialect became influenced by both Gaelic and Norn[75] and is generally spoken in the lowlying land to the east of a line drawn from Clyth Ness to some 4 miles (6 km) west of Thurso.

Other sources state: According to the 2011 Scotland Census, 282 (1.1%) residents of Caithness age three and over can speak Gaelic while 466 (1.8%) have some facility with the language.

In 2008, eight of the ten Caithness representatives to the Highland Council tried to prevent the introduction of bilingual English-Gaelic road signs into the county.

Gaelic-speaking Councillor Alex MacLeod, at the time representing Landward Caithness in the Highland Council, referred to it as "an extreme anti-Gaelic incident".

[85][86] The John O'Groat Journal and The Caithness Courier are weekly newspapers published by Scottish Provincial Press Limited[87] trading as North of Scotland Newspapers[88] and using offices in Union Street, Wick (but with public reception via Cliff Road) and Olrig Street, Thurso.

The Courier was printed, almost by hand, in a small shop in High Street, Thurso until the early 60's by Mr Docherty and his daughter.