You don't have to go far off of the hellish A47 between Norwich and Yarmouth to come out into an utterly rural and remote corner of Norfolk. This is partly sleight of hand, because the narrow lanes which leave the busy road are so winding that they make you think you've come further than you have. Also, you might expect this area between the marshes and the broads to be flat and open; but here the landscape rolls, a patchwork of hedged fields and copses. In the late summer, there was a balmy restlessness, the soothing warmth of the sun competing with the wind from the North Sea ruffling and rustling the long grass. All Saints is set in a secretive graveyard on a rise above a lattice of country lanes. From a distance it appears a sentinel; but, closer to, the aspect softens, and the church reveals itself as a humble little round-towered building, with much that is old about it, but also the simple mendings and making dos of later generations. I was particularly struck by the use of red brick, both in the elegant window in the western side of the Norman tower (is it 17th century?) and the moulding inside the opening of what is otherwise a humble south porch. When I first came this way I bemoaned the fact that Hemblington church was kept locked, but I am happy to report that it is now open every day. Certainly, Hemblington is a remote parish, and its church a remote church, and trusting strangers is a risk - and Faith itself is a risk, of course. But the great medieval treasures of Hemblington are not the kind that can be carted away in the back of a white van.

The first is one of a number of very interesting, even idiosyncratic, fonts in this part of Norfolk. These do not appear to be part of a series, although this one does bear a strong resemblance to that nearby at Buckenham. They do suggest, however, that there was an abundance of stonecarvers working in this area in the 15th century, and that parishes were able to express their independence and individuality in their choice of subject. The Reformation would put a stop to that.

The Hemblington font was recoloured lightly in the 1930s under the eye of Professor Tristram. It is a great celebration of Saints; there are seven seated on the panels of the bowl, and eight more standing around the shaft. The eighth panel subject is a beautiful Holy Trinity, with God the Father seated holding his crucified Son between his knees, while the dove of the Spirit descends. It is a charming image; there is another on the font at Acle a few miles off. Among the Saints on the panel are St Augustine, St Edward the Confessor, St Barbara, and a striking St Agatha - she sits with her breasts bared, a sword descending. Among those around the shaft are St Lawrence with a finely carved grid iron, St Leonard with his manacles, St Margaret dispatching a dragon with her cross, St Catherine with her wheel and sword, St Stephen and St Mary Magdalene.

If there was only the font, Hemblington would be a must-see for anyone interested in the late medieval period. But just as the font demonstrates the enthusiasms of the cool, rational 15th century, so there is evidence of the shadowier devotions of a century earlier. This is the best single surviving wall painting of the narrative of St Christopher in England. The giant figure bestrides the river opposite the south doorway, just as he does in about twenty churches in this part of Norfolk, but here his staff has become a club, and on either bank there are smaller scenes depicting events in the Saint's story. those on the west side, recalling his life as a pagan before conversion, are all but obliterated. Those on the east side, however, are marvellously well-preserved, vivid and immediate in their clarity. They show the trials and tribulations he underwent in his life as a Christian, including the occasion on which two women were sent to tempt him in prison, and another where he is led to the executioner's sword. Another shows him tied to a tree being flogged, an echo of the scourging of Christ; another shows him being shot through with arrows, which would have immediately brought to mind the martyrdom of their own dear St Edmund to the medieval East Anglians.

The donors who paid for the font, in that great, late medieval attempt to reinforce Catholic orthodoxy in the face of local abuses and superstitions, are probably among those remembered by brass inscriptions in the nave.

And this must have been a busy parish in those days, for will evidence reveals that there were three guild altars where lights burned for the dead. We can even trace where these guild altars may have been, for on the north side of the nave there is a piscina, and connected to it is a pedestal, where a statue of a Saint would have stood. Such things were probably destroyed in the 1530s by orders of the increasingly paranoid King Henry VIII; those that survived would have fallen to the orders of the enthusiastically puritan advisors of his son, the boy King Edward VI a decade later. It is appalling to think of the richness that once was, not just here, but in thousands of village churches all over England. So much lost, so much wilfully destroyed. Hemblington has retained more than most, and the church is a fascinating testimony to the mindset of late medieval East Anglia. But even without these great treasures, All Saints is a charming, rural building that speaks as loudly of the Victorian villagers who paid for, and probably worked on, its restoration as it does of their mysterious Catholic forebears. I stood for a moment imagining the blacksmith and the plowboy, the wheelwright and the carpenter, sitting in the pews for Divine Service. And then, after a chat with the modern custodians, we headed on for North Burlingham.