[3] The unrestored 12th-century stone church serves a rural area near the River Arun and sits apart from the hamlet next to the ancient manor house.

[3] When the vestry was being built, five soldiers were found buried next to the church wall: they had been killed at the Battle of Greatham Bridge during the English Civil War.

[6][11] Greatham Church is a tiny, primitive, unrestored building dating from the "Saxo-Norman overlap" period when Anglo-Saxon architecture was giving way to the Norman style.

[3][6][7][12] The writer Arthur Mee was once told not to mistake the church for a haystack:[5] set in the middle of fields and on its own apart from the manor house,[2] it has an extremely basic and modest feel—amplified by its lack of electricity and piped water.

[6] The walls, of unequal length and thickness,[6] are principally of ironstone with some chalk, flint, Roman-era masonry and rubble, local (Pulborough) sandstone and Horsham Stone.

[2][12] A good example of a Gothic Revival-style[2] two-decker pulpit,[13] in dark wood and built in the early 19th century (possibly around 1820),[12] also survives, as do box pews of the same era.