IF you look down on the attractive town of Callander from high on the adjacent Callander Crags, the most prominent building is St Kessog's Church.

With its fine, high spire the church dominates the centre of town.

St Kessog's ceased to be a working church more than 20 years ago. Its interior was largely stripped out and it is now the town's tourist information centre. Similar fates have befallen fine churches - many of them of outstanding architectural merit - all across Scotland. A traveller entering Scotland at the little town of Coldstream, just yards north of the Border, would pass three churches almost immediately. The first, admittedly down a side street, is now a bar. A little further on, there are two substantial churches on either side of the main street. One is now a community centre; the other is still in use as a church.

This, at one of Scotland's gateways, is all too typical of a country which is perhaps more over-churched than any other Christian nation (if it still is a Christian nation, that is; as last week's census results indicated, the trend is very much towards a secular society).

But the problem for Scotland's churches is not so much secularisation as an unfortunate historical legacy. There was a ridiculous, competitive, ostentatious burst of church building in the latter half of the 19th century, following the Disruption in the national Kirk.

Many regard the Disruption as a noble event. I cannot agree. It led to the an extravagant orgy of church creation - it was a fine time to be an ecclesiastical architect, and many of these architects were outstanding - when both the new "free" and the old national church should have been spending their considerable resources on helping and assisting the new proletariat. The ravages of early, over-rapid industrialisation left Scotland with an exploited working population that was often ignored by the churches, despite the commendable efforts of the city missions.

Meanwhile many communities - small towns and single parishes within cities and bigger towns - had two churches when they barely needed one.

Other parts of our developing cities and towns were left more or less unchurched. In the 20th century it was discovered that churches were often in the wrong places. New churches were built where they were needed, but now they too are becoming redundant. The Catholic Church, which barely existed in early industrial Scotland, had also embarked on a programme of church building.

So Scotland now possesses old - and not so old - churches that are used as nightclubs, transport depots, indoor climbing centres, fitness clubs, housing, shops and goodness knows what else.

The most spectacular redundant building is not however a church, but St Peter's College at Cardross, designed by the celebrated ecclesiastical architects Gillespie Kidd and Coia as a fine new seminary for the Catholic Church in the early 1960s. The building was acclaimed as a work of international architectural significance.

It closed as early as 1989. After a brief reinvention as a rehabilitation centre, it was left to decay and rot. Perhaps more than any other site, it symbolises the precipitate decline of Christianity in Scotland.

Yet the real scandal is the virtual closure of too many buildings which are still, supposedly, used as churches. Seven or eight hours a week is not good enough. For fine buildings to be so rarely used is absurd. Just last week, on a busy weekday morning, I went round the largest Borders town, Hawick. I visited seven churches before I found one that was open, and that was just because the organist was rehearsing for the Sunday service. Some of these churches had noted interiors. Some were prominent buildings. They were closed to the public, useless and bereft, a blight on the town.

Now the Church of Scotland is facing reality and putting no fewer than 77 churches up for sale. Meanwhile more effort could be made to put its many other churches - some of them very distinguished buildings, inside and out, which often dominate their environments - to decent and constructive use during the week.