In May 1952 Willi Ruhland, a member of staff at the Helms-Museum, was walking the municipal clay pit at Ovelgonne, a district of Buxtehude in Lower Saxony, when he noticed a dark discolouration in a freshly cut clay wall on the pit's north side. Discolouration like that means disturbed ground. Digging it out revealed an irregular pit about 150 centimetres deep and 150 centimetres across, its backfill jumbled with potsherds, lumps of charcoal, clay and stones - the unmistakable signature of an Iron Age rubbish hole. Halfway down, among the debris, lay the charred remains of a bread roll. Nobody had buried it with ceremony. Somebody had simply burnt the baking and thrown it away, and the charring that ruined it as food is the only reason it survived at all.

The surviving fragment measures 35 millimetres long, 22.94 wide and 11.44 high, and the tip of its one remaining end is missing. Its upper surface is pearl to slate grey; the underside runs grey to black. Along the top is a fine, slightly curved incision of exactly the kind bakers still cut to stop a loaf tearing as it rises in the oven. Near the centre of the top sits a shallow depression two millimetres deep and about three and a half by two and a half millimetres across, pressed in with a round tool held at roughly forty-five degrees. A second such hole was probably on the missing half. Sandy deposits inside the break show the roll was snapped apart long before anyone found it. Working from a large body of archaeological bread finds and allowing about fifteen percent shrinkage from the charring, the Swiss baking historian Max Wahren reconstructed the whole roll at roughly 70 by 45.88 by 22.48 millimetres - a small pointed roll, a Spitzweck, of the sort a modern baker would recognise on sight.

The analysis is where this fragment stops being a curiosity and starts being a document. Under the microscope the flour proves to be wheat, very finely ground and sifted, carrying only remarkably small traces of wear from the millstones - a fineness approaching that of modern flour, from people working with hand querns. The dough was thoroughly kneaded and shows very little porosity, which rules out both wild yeast fermentation and sourdough; if anything lightened it, egg white or fat is the likeliest candidate. There was no pronounced crust. Charcoal traces caught in the pores of the base show it was baked directly on a stone oven floor that had been swept, but not swept perfectly, and the pattern of scorching indicates fierce top heat by today's standards. A radiological examination carried out in Bern showed the surface incision widening slightly as it goes inward, and turned up two small metal particles, each around three millimetres across, embedded in the dough. Nobody has explained them.

The dating does not come from the bread. It comes from the pottery thrown away beside it: the sherds in the pit match diagnostic vessel forms of the early Pre-Roman Iron Age, placing the whole deposit somewhere around 800 to 500 BC. That is worth being clear about, because the roll's fame rests on its age and its age rests on typology rather than on the bread itself. Wahren's judgement was that the Ovelgonne find is the oldest fine baked product in Europe surviving in the flesh, made in the form of a pointed roll and probably carrying ritual or religious meaning. His reasoning turns on the details a careless baker would not bother with - the fineness of the flour, the scoring, and above all the pressed dimple. Comparable impressed holes are known from an ancient Egyptian find of roughly 2000 to 1778 BC and from the bread depicted in the 6th-century mosaics of the Basilica of Sant'Apollinare Nuovo in Ravenna. On this scrap from a Lower Saxon clay pit, the technique appears earlier than anywhere else in prehistoric Europe.

The fragment is on permanent display at the Archaeological Museum Hamburg, the Helms-Museum, in Hamburg-Harburg, shown in the food section alongside a full-size reconstruction of what the intact roll would have looked like. The pairing is the point. Alone, the burnt scrap communicates nothing; next to the reconstruction, you can see the pointed ends, the cut along the back, the thumbed hole - and the distance between an Iron Age kitchen and a modern bakery shelf shrinks to almost nothing. Somebody in the marshland behind the Elbe, two and a half millennia ago, cared how their bread looked.