St. David's Episcopal Church, often known as St. David’s at Radnor or, less often, as Old St. David's, is a parish of the Episcopal Church in the United States of America, founded in the early 18th century and named after the Patron Saint of Wales. A Book of Common Prayer, given as a gift to Lydia Leamy in 1854, refers to St. Davids as "Radnor Church". It has grown to be the largest congregation in the Episcopal Diocese of Pennsylvania, with some 950 active families and 3,000 members. The original church building, built in 1715 and the subject of a Longfellow poem, still stands. It is in nearly the same condition as when it was built, several new buildings having been constructed to house the growing congregation. The adjacent graveyard is a part of the historic site. The church property i