Aligned on a south-west to north-east axis, it measures 8 miles (13 kilometres) in length and reaches 3 mi (5 km) at its widest point.

Intrusive igneous rocks are represented by diorites and monzonites of the 'North Britain Siluro-Devonian Calc-Alkaline Dyke Suite' seen at Scalasaig and Balnahard.

[6][7] Although Colonsay appears bare and somewhat forbidding on approach from the sea, its landscape is varied, with several beautiful sandy beaches, and a sheltered and fertile interior, unusually well-wooded for a Hebridean island.

Similar sites in Britain and its dependencies are known only at Farnham in Surrey and at Cass ny Hawin, near Ballasalla on the Isle of Man.

"[11] A Viking grave at Kiloran Bay, including a boat and silver burial goods, was discovered in 1882 on land belonging to John MacNeil.

In 1904 the estate of Colonsay was bought by Donald Smith, 1st Baron Strathcona and Mount Royal from the trustees of the late Major-General Sir John Carstairs McNeill V.C.

Colonsay House is currently occupied by Alexander Howard, 5th Baron Strathcona and Mount Royal and his family.

Scalasaig, Glassaird, Kiloran and Colonsay House had local generators installed by Messrs Scott of Glasgow.

Recently there has been a growth of tourism as the mainstay of the island's economy, with numerous holiday cottages, many of them owned and managed by the Isle of Colonsay Estate.

Colonsay's best known beach, Kiloran Bay, is a vast stretch of golden sands and draws locals and tourists alike while maintaining an isolated and peaceful atmosphere.

Current projects include running the island's coal supply and only petrol pump, a major Rhododendron ponticum eradication programme and a feasibility study into the possibility of improving the harbour and surrounding area.

[28] In November 2006 a construction worker from Glasgow was arrested and confessed to theft by housebreaking, having entered an unlocked house and stolen £60 in cash.

directed by Michael Powell and Emeric Pressburger was principally shot on Mull and references the fictional "Isle of Kiloran", which was based on Colonsay.

[35] A similar event occurs every autumn, called "Connect with Colonsay", which runs over a three-week period in October.

In 2012 the island staged its first annual book festival which featured, amongst others, Alexander McCall Smith, James Robertson, and Scots Makar Liz Lochhead.

[36] The island is home to a herd of wild goats, and is known for its bird life including black-legged kittiwakes, cormorants, guillemots, corncrakes and golden eagles.

The Scottish Government introduced the Bee Keeping (Colonsay and Oronsay) Order 2013 to prevent cross breeding with other honeybees (Apis mellifera) and to protect it from diseases common on the mainland.

The Environment and climate Change Minister Paul Wheelhouse MSP said: "The Bee Keeping Order illustrates how our non-native species legislation can be used to protect our native wildlife.

[38] They were collected from across Scotland in the previous thirty years, genetic analysis has shown Australian and New Zealand A. m. ligustica introgression.