Originally called The The Welsh Calvinistic Congregational Bethel Church of Delhi, this congregation later became The Radnor Congregation Church and finally Radnor Congregational United Church of Christ. It grew out of Congregational prayer meetings held in homes beginning in 1820, with Rev James Davis preaching only in Welsh. The first church building, a frame structure, was erected in 1841. In 1864 it was replaced by the present brick building, constructed by Thomas Griffith for a cost of $3000 when the congregation had 260 members. Hand-shaped bricks made from clay from the northwest portion of the property were used in its construction. In 1905 a distinctive wooden portico was added to the front, and stained-glass memorial windows were installed in honor of sponsoring families who were Welsh immigrants or first-generation Welsh Americans. In its early years, the sanctuary was lighted by a large chandelier raised and lowered by rope and pulley for lighting, and in 1918 the building was wired for electricity and the chandelier was converted. In 1948 the church joined a national denominational merger and took the name Radnor Congregational United Church of Christ, and a one-story room for Sunday school expansion was added to the rear. Over the years, further interior improvements included central heating, a redecorated sanctuary, a choir balcony, new pews, a kitchen, and a restroom.