All Saints Church, Thorpe Abbots, Norfolk

Of about 180 round west towers on English churches, all except five are in East Anglia and most are flint built. Until recently it was widely accepted that most were Norman and that where the belfry stage was octagonal it was a post- Norman addition. Over 50 medieval round towers have octagonal upper stages and recent studies of their fabric suggest that in more than 20 the circular stage is post-Norman and the octagon contemporary with it. In all of these, except for three where the tower arch was probably originally a west nave entrance, or the whole tower replaces an earlier one, a pointed tower arch corroborates a post-Norman date. The number of towers with octagonal stages with lancet or early-c 14th- belfry openings that are contemporary with the circular stage compared to those with added c 15th-century belfries suggests that the architectural trend of an octagonal belfry stage on a circular base first appeared as towers purpose-built to that design - to be followed later by those in which an octagon apparently replaced the original circular belfry of a Norman tower.