The rock is an eighty ton granite boulder perched on the edge of the cliffs overlooking the Atlantic ocean, on a headland one mile south of the village. The rock is finely balanced due to the actions of weathering, and prior to its restoration in 1824 it could be rocked by applying only a little pressure .
The name Logan Rock is also applied to the surrounding tip of the headland, as well as the logan stone itself. Cripp's Cove lies to the east beneath the rock. The headland is also an Iron Age promontory fort called Treryn Dinas, defended by three ramparts. A number of islands are located around the edge of Logan Rock including Great Goular, Horrace, and Seghy.
Some have suggested that it comes from a Cornish expression for the movement that someone makes when drunk. Davies Gilbert writes:
It should also be noted that the name for rocking stones could be a modified form of the Danish word "logre," which means 'to wag the tail,' and this suggests possible Norse origin. Danes in particular established a kingdom in Great Britain before 1000 A.D., Norway maintained nominal control over the Hebrides in northern Scotland until the late Middle Ages, and Vikings frequently raided along the British coastal areas between 800 and 100 A.D. Thus, a Norse origin for the word Logan, while speculative, cannot be ruled out.
The Logan Rock is one of the best known rocking stones for several reasons. For example, Modred, in William Mason's dramatic poem "Caractacus," addressing the characters Vellinus and Elidurus, says of the Logan Rock:
However, another reason that the Logan Rock of Treen is remembered is that it was the center of a famous drama. In April 1824, Lieutenant Hugh Goldsmith, R. N. (nephew of the famous poet Oliver Goldsmith), and ten or twelve of his crew of the cutter HMS Nimble, armed with bars and levers rocked the huge granite boulder until it fell from its cliff-top perch. Goldsmith was apparently motivated to disprove the claim of Dr. Borlase, who wrote in Antiquities of Cornwall in 1754 that:
Goldsmith was determined to demonstrate that nothing was impossible when the courage and skill of British seamen were engaged. The Logan Rock fell and was caught in a narrow chasm.
This upset the local residents considerably, since Logan Rock had been used to draw tourists to the area. Treen had become a lucrative tourist destination. Sir Richard R. Vyvyan was particularly unhappy. The local residents demanded that the British Admiralty strip Lieutenant Goldsmith of his Royal Navy commission unless he restored the boulder to its previous position at his own expense.
However, Davies Gilbert persuaded the Lords of the Admiralty to lend Lieutenant Goldsmith the required apparatus for replacing the Logan Rock. The Admiralty sent thirteen capstans with blocks and chains from the dock yard at Plymouth, and contributed £25 towards expenses. Gilbert also raised more funds
After months of effort, at 4.20pm on Tuesday, the 2nd of November, 1824, in front of thousands of spectators and with the help of more than sixty men and block and tackle, the Logan Rock was finally repositioned and returned to "rocking condition" (Michell 1974). Apparently the total final cost of this enterprise was £130 8s 6d. However, it is not clear how much of the remaining £105 Goldsmith had to make up out of his own pocket. For some time after, the rock was kept chained and padlocked, but eventually these restrictions were removed, and the rock was set free. However, it apparently no longer vibrates or "logs" as easily as it did before.
Tourism declined and this was blamed on the condition of Logan Rock. For a while, Treen was nicknamed 'Goldsmith's Deserted Village'. The anchor holes used to haul the huge rock back up the cliff are still visible in the surrounding rocks.