Senghenydd (Welsh: Senghennydd, IPA: [sɛŋˈhɛnɪð]) is a former mining village in the community of Aber Valley in South Wales, approximately four miles northwest of the town of Caerphilly.

With the closure of the coal pits in the second half of the twentieth century, most people in the village now commute outside the Aber Valley for employment.

Ifor Bach's great grandson Llewelyn Bren (Llewelyn ap Gruffudd ap Rhys) was the last Welsh lord of Senghenydd, but lost control of his lands after the six-week siege of Caerphilly Castle[citation needed] and a brief battle at Castell Morgraig, a Welsh-built castle at Cefn-Onn ("Ash Ridge") which was possibly built by the Lords of Senghenydd.

In October 1326, after the successful rebellion led by Roger Mortimer, the Despensers and Edward had further cause to regret their actions in Glamorgan after they were forced to flee there.

Senghenydd, along with its neighbouring village Abertridwr, make up the majority of the Aber Valley in the South Wales Coalfield, which became urbanised in the 1890s, when the Universal and Windsor collieries were sunk in this region.

[5] On 14 October 1913, Senghenydd suffered the worst mining disaster in Britain's history, when a second gas explosion occurred at the Universal Colliery, resulting in the loss of 439 lives, and the death of one rescuer.

Since 1979, a representative sample of adult males born between 1918 and 1938, living in Caerphilly and the surrounding villages of Abertridwr, Bedwas, Machen, Senghenydd and Trethomas, have participated in the study.

A notable report was on the reductions in vascular disease, diabetes, cognitive impairment and dementia attributable to a healthy lifestyle.