Adpar was formerly called Trefhedyn and was an ancient borough in its own right. Adpar is noteable because Isaac Carter (d. 1741) the printer and native of Carmarthenshire established the first permanent printing press in Wales here in 1719. As far as is known the first two publications to issue from the press were Cân o Senn i’w hen Feistr Tobacco by Alban Thomas (q.v.) and Cân ar Fesur Triban ynghylch Cydwybod a’i Chynheddfau. At least three other (and larger) works were produced by the Adpar press before it was transferred to Carmarthen about 1725.
Also the last duel to take place in Cardiganshire happened there in 1814.