Aghadowey Presbyterian Church sits in a rural area, in the townland of Ballywillan in the Parish of Aghadowey, County Londonderry.
It is a large rectangular barn like church, on either side of the church are the former schools; a Boys school established in 1824, and a Girls school established in 1857.
The long history of the church demonstrates the social history of the area, especially emigration. 1718 saw the first organised mass emigration from this area led by Revd James McGregor. Many people return to trace their forebears to see the place they worshipped and see their family names on grave stones. They may have seen family names in Old Minute Book 1702-725. A New Zealand couple whose forbearers had lived in The Mill Row at Ballywillan said 'I cant believe we found this place where they were'.
In the 18th century the linen Industry played a major role in the area and this is reflected in the size of the church which can seat 1000 people.