And so we came to Braydeston. It was the end of the Historic Churches bike ride day 2007, and all over England the welcomers were taking in the sign boards, washing out the squash jugs and putting the last of the biscuits back in the tin. We had visited 19 churches so far; a modest number, perhaps, on this day when virtually all are open, but we had found the Anglicans of the Yare Valley to be a particularly friendly bunch, detaining us with their conversation and offers of cups of tea. They seemed genuinely pleased to see us, although this may well be because ordinarily most of their churches are kept locked, unlike the majority in Norfolk. We had seen Braydeston off on its gentle hilltop several times during the day, particularly from Blofield, where the great tower is less than half a mile from Braydeston's little boxy one. But that is as the crow flies, or the rambler walks, or the 19th century Rector plods on his horse from one Divine Service to another. To get from one to the other by car, it is necessary to go out along the narrow, doglegging lanes between fields already ploughed, a smell of earth and the gathering coldness of a late summer afternoon.

Braydeston is one of those churches that few people visit, I would hazard a guess. It isn't particularly well-known for anything historic or interesting, and the setting is so lonely that it is unlikely too many pilgrims or strangers turn up to rattle at its locked door in frustration.

We came down the track and parked, and a nice lady came out to the gate to welcome us. You could sense that she was one of those stalwarts of rural churches. These are the people who count the collection, make sure the gutters are cleaned out, fill in the health and safety forms, organise the flower rota, and so on. They are the reason why some rural medieval churches look as if they have a busy life, and yet others have been abandoned. It often has little to do with the size of the village, or the number of people in the congregation. Ultimately, it is about the commitment of a small number of people. God help their churches when they go.

As it turned out, this energetic lady had also written the guidebook, and was very knowledgeable about her building. St Michael rides its gently sloping hillside like a great ship, the chancel lifting out of the waves. There was obviously once an aisle on the south side, and although there is the ghost of a Norman window on the north side, the church looks mostly the work of the 13th century. For a moment, you might think the same of the rather stark tower, but in fact it appears to be the result of a bequest in the late 15th century.

The interior is rather narrow, and in the late afternoon there was not much light getting inside. But the east window, depicting Faith, Hope and Charity, is excellent, and provides a lovely focus for worship. It was installed as a war memorial in the 1920s.

There was quite an early 19th century restoration here, and it is a restrained one, most fitting in this quiet place. The most unusual feature is the stumpy font; the top part is an octagonal bowl in the Decorated style, probably on the eve of the Black Death, but the pedestal is a huge thing, as wide as the bowl. I couldn't make out if they were two separate pieces of stone. Is it original, or was it added later to replace a collonade?

The little screen is delicately carved, and a beautiful pelican in her piety plucks at her breast to feed her chicks with her own blood. On the wall beside it is a reminder of this building's preaching house days, the stand for the hourglass which made sure ministers didn't skimp on the sermon. The simplicity of the interior makes the few details stand out, including the handful of memorials; rather sad ones, I am afraid. One is to two of the sons of the Reverend Thomas Drake, who, in 1830, were drowned by the upsetting of a boat at Langley in this neighbourhood. It seems that their father was already dead, for this humble tablet to commemorate the melancholy event is erected by Martha Stewart, relict of the above. Further to the west is a reminder of a tragedy of almost a century later. Walter Meire, the 25 year old son of Walter and Hannah Meire of Verne House in Brundall, was killed in action at the Battle of Loos in September 1915. His body was never found, and he is remembered on the Loos memorial. A simple wooden plaque remembers the two boys from the parish killed in World War Two.

It was all lovely and interesting, a real touchstone down the long generations of the parish of Braydeston.

I stood outside, and looked out across the rolling fields towards Blofield's tower. This was the end of my fourth Historic Churches bike ride day in Norfolk, and by chance it happened that Braydeston was my 700th Norfolk church. There will be many more to come, but so far it has been a privilege to immerse myself in this great treasure house of a county's faith and history, what the writer Simon Jenkins has called the greatest folk museum in the world. If we are in the last days of the Church of England - and its demise has been greatly exaggerated, of course - what will happen to these wonderful buildings? I thank God that there is a greater will to preserve them than there was in the 1960s, for example.

19th century philosophers argued that Faith would die; but of course, this hasn't happened, at least not yet. Many of the Christian denominations are undergoing unprecedented growth, and people are forever 'surprising a hunger in themselves' to seek out holiness. And there are new religions; consumerism, hedonism and humanism, to name but three, which may seem evil in their ways to Christians, but which are eagerly reached for by those seeking to satisfy the emptiness in their lives. And what of the future? As well as changing patterns within its own sphere, Christianity is going to have to cope with the emergence of popular scientific atheism as a real threat. For the first time since the days of Communist Russia and Nazi Germany, we regularly have philosophers and psychologists appearing in the media to tell us that our Faith is a form of mental illness, that bringing up our youngsters in the Christian tradition is a form of child abuse, and that the battle between good and evil will be fought with genetics. God help us if these people ever achieve political power.

Meditating on this rather depressing development, I wondered what a medieval Braydestoner would have seen if he had looked out towards Blofield on a day like this, perhaps in the early years of the 16th century. It would have looked much the same, I suppose. There would have been fewer trees, the fields would have been smaller, and there would have been more people on them, for the annual ploughing took far longer then than it does now.

What would he have felt? The same cooling, evening breeze coming from the east as me, perhaps. What would he have smelt? the same sharpness of the cloven earth, the sweet sourness of the leaves begining to turn, the year beginning to wind down. And what would he have heard?

It was nearly six o'clock. I imagined the angelus bell, which has not rung at Braydeston for almost half a millennium, jangling out its brisk trot across the fields, and the ploughing workers pausing for a moment to stand - not in prayer exactly, more in an attitude of meditation, a moment to recollect who they really were, and that there was more to life than ploughing and sowing and reaping and birth and death and the eternal struggle to survive. That they were, in fact, God's People. And then they would return to their work, shadowy figures now in the deepening mist, as other distant bells took up the call, further and more distant, all the way across lost Catholic England.