In 1752, Harris, one of the foremost leaders of the Welsh Methodist revival, established a Christian community there known as Teulu Trefeca (the Trefeca family). The additions to his family house were in a very unusual Gothic architecture style, one of the first examples in Wales, completed by 1772.
Selina, Countess of Huntingdon, established a theological seminary nearby in 1768, which transferred to Cheshunt in 1790. The building used is now a farm. Cheshunt College was later affiliated with the Congregational Union of England and Wales. It moved again in 1906 to Cambridge and merged with Westminster College, Cambridge in 1967.
Thomas Charles had tried to arrange for taking over Trevecca College when the trustees of the Countess of Huntingdon's Connexion removed their seminary to Cheshunt in 1791; but the Bala revival broke out just at the time, and, when things grew quieter, other matters pressed for attention. A college had been mooted in 1816, but the intended tutor died suddenly, and the matter was for the time dropped. Candidates for the Connexional ministry were compelled to shift for themselves until 1837, when Lewis Edwards (1809–1887) and David Charles (1812–1878) opened a school for young men at Bala. North and South alike adopted it as their college, the associations contributing a hundred guineas each towards the education of their students. In 1842, the South Wales Association opened a college at Trevecca, leaving Bala to the North; the Rev. David Charles became principal of the former (from 1842 to 1863), and the Rev. Lewis Edwards of the latter. After the death of Dr Lewis Edwards, Dr. T. C. Edwards resigned the principalship of the University College at Aberystwyth to become head of Bala (1891), now a purely theological college, the students of which were sent to the university colleges for their classical training. In 1905 Mr. David Davies of Llandinam, one of the leading laymen in the Connection, offered a large building at Aberystwyth as a gift to the denomination for the purpose of uniting North and South in one theological college; but in the event of either association declining the proposal, the other was permitted to take possession, giving the association that should decline the option of joining at a later time. The Association of the South accepted, and that of the North declined, the offer; Trevecca College was turned into a preparatory school on the lines of a similar institution set up at Bala in 1891. It is now a residential retreat centre, Coleg Trefeca.
In 1872, a Harris Memorial Chapel was added to Trefeca, designed by R. G. Thomas of Menai Bridge.
Howell Harris Museum
The Howell Harris Museum is located at Coleg Trefeca. Open by appointment, the exhibits focus on the life of Howell Harris and the community of Teulu Trefeca that he founded.
- Samuel Eyles Pierce, English preacher, theologian, and Calvinist divine