It is sometimes very difficult to work out how an ancient building became what we see today. Changes such as adding an aisle, replacing the roof or building a tower usually involved sweeping away parts of the original structure, making it hard to envisage how the building grew.
The remote and lovely church at Up Marden is very simple to ‘read’, except for one mystery. The building is almost completely 13th century, unaltered and mercifully unrestored. It doesn’t even have electricity. Indeed, whereas most church guide books consist of a long list of the changes the centuries have wrought, the guide to Up Marden has lengthy tales of the many disputes over repair bills, so perhaps we have Sussex tight-fistedness to thank for the unmolested beauty of the building with its simple lancet windows and wagon roof.The only loss is the wall painting, of which only a fragment survived the Reformation.
Ian Nairn in Buildings of England said that the triangular arch was inserted later, to prevent a collapse. He wrote: “The triangular arch is not, as it looks, Saxon, but an emergency 16th century repair to the 13th century arch which can be seen above it.”
Nairn is not entirely certain, however. A footnote says: “It could conceivably be Saxon work renewed: the VCH [Victoria County History] suggests that it might have come from the former church at West Marden.”