Thomas Price commenced his ministry in 1845.
As the membership grew the building became too small so Carmel was handed over to a smaller English speaking congregation while a new chapel, Calfaria, was built nearby.
The new chapel was designed by Thomas Joseph, a colliery engineer from Hirwaun, cost £1,400 to build and seated 840.
The building was extended in 1859 and the adjacent Calfaria Hall built in 1871.
The first service was held at Calfaria on 8 February 1852.
By this time, Price had become a leading figure in public life, primarily as a result of his very public criticisms of the 1847 Education Reports and the evidence given to the commissioners by the vicar of Aberdare, the Rev John Griffith.

At one time in the nineteenth century, Calfaria had over a thousand members but many hundreds were transferred to branch chapels established at the instigation of Thomas Price.
In 1855 the Heolyfelin Baptist Church was formed as a branch of the Hirwaun Baptist Church; and in 1856 91 members from Calfaria were transferred to form the English Baptist Church at Carmel, Aberdare.
Bethel, Abernant, was opened in 1857.
In 1849 121 members were transferred to form Gwawr, Aberaman; in 1855, 89 were released to start a cause at Mountain Ash, and in 1862, 163 were released to strengthen Bethel, Abernant; in the same year 131 were released to form a church in Ynyslwyd; in 1865 49 were transferred to form Gadlys Church.
927 altogether were released from Calfaria to form churches in various parts of the district.
Price, however, ensured that the unity of the Baptist 'family' of churches was maintained by such activities as Baptismal services in the river Cynon and annual eisteddfodau.
In 1913, a local resident recalled:
"I remember that once a month on Sunday afternoons, Dr. Price, the Baptist minister, used to baptise his recent converts in the Cynon River, alongside the iron bridge at the bottom of Commercial Street.
I have seen as many as 25 or 30 converts, men and women, on the same afternoon.
On these occasions the whole of the Baptist community used to meet at the chapel and march ii procession through the streets with the converts, the men converts being attired in long black robes and the women in white.
They marched through the streets from the chapel to the place of baptism singing hymns.
As a matter of course, large crowds gathered on the river banks to witness the immersions."

Calfaria retained its pre-eminence among the Baptist churches of the valley although Price's prestige was somewhat undermined by his failure to support Henry Richard at the 1868 General Election.
In 1869, Price visited the United States for six months with his daughter Emily.
His funeral in 1888 was one of the biggest seen in the valley.
Thomas Price commenced his ministry in 1845. As the membership grew the building became too small so Carmel was handed over to a smaller English speaking congregation while a new chapel, Calfaria, was built nearby. The new chapel was designed by Thomas Joseph, a colliery engineer from Hirwaun, cost £1,400 to build and seated 840. The building was extended in 1859 and the adjacent Calfaria Hall built in 1871. The first service was held at Calfaria on 8 February 1852. By this time, Price had become a leading figure in public life, primarily as a result of his very public criticisms of the 1847 Education Reports and the evidence given to the commissioners by the vicar of Aberdare, the Rev John Griffith.
At one time in the nineteenth century, Calfaria had over a thousand members but many hundreds were transferred to branch chapels established at the instigation of Thomas Price. In 1855 the Heolyfelin Baptist Church was formed as a branch of the Hirwaun Baptist Church; and in 1856 91 members from Calfaria were transferred to form the English Baptist Church at Carmel, Aberdare. Bethel, Abernant, was opened in 1857. In 1849 121 members were transferred to form Gwawr, Aberaman; in 1855, 89 were released to start a cause at Mountain Ash, and in 1862, 163 were released to strengthen Bethel, Abernant; in the same year 131 were released to form a church in Ynyslwyd; in 1865 49 were transferred to form Gadlys Church. 927 altogether were released from Calfaria to form churches in various parts of the district. Price, however, ensured that the unity of the Baptist 'family' of churches was maintained by such activities as Baptismal services in the river Cynon and annual eisteddfodau. In 1913, a local resident recalled:
"I remember that once a month on Sunday afternoons, Dr. Price, the Baptist minister, used to baptise his recent converts in the Cynon River, alongside the iron bridge at the bottom of Commercial Street. I have seen as many as 25 or 30 converts, men and women, on the same afternoon. On these occasions the whole of the Baptist community used to meet at the chapel and march ii procession through the streets with the converts, the men converts being attired in long black robes and the women in white. They marched through the streets from the chapel to the place of baptism singing hymns. As a matter of course, large crowds gathered on the river banks to witness the immersions."
Calfaria retained its pre-eminence among the Baptist churches of the valley although Price's prestige was somewhat undermined by his failure to support Henry Richard at the 1868 General Election. In 1869, Price visited the United States for six months with his daughter Emily. His funeral in 1888 was one of the biggest seen in the valley.
Calfaria, Aberdare