Adam Lawrence visited Steve Marnoch and Jonathan Gaunt's mountainous challenge in Spain.

Some articles write themselves.

Occasionally as a golf writer you visit a course that is either so overwhelmingly wonderful, or so horrific, the response is almost automatic. Most courses, though, mix wonder and horror.

But for me never have the two been so starkly opposed as the day I saw the new course at the private La Zagaleta club in the mountains above Marbella.

The club at La Zagaleta is pretty unusual in European terms. A huge estate that formerly belonged to Saudi arms dealer Adnan Khashoggi, the property is being transformed into a sundrenched retreat for the almost-as-wealthy. With an 18 hole course built in the late 1990s by American architect Bradford Benz, and with unbuilt villa plots starting at €1.5 million, the club is a very quiet, very private sanctuary for its members.

But herein lies the first oddity. Play on the existing 18 is beyond light – on average only a few rounds a day. So why,then, did the club feel it necessary to spend €21 million on building another golf course? The answer, as so often, lies in real estate. The new course has opened up – and provided planning consent for – another 75 villa sites. Consider the prices mentioned and do the maths. But being further up the mountain, the land allocated to the new 18 was far more extreme than that used by the existing course. Which helps to explain why the cost stretched from the originally budgeted €10m to the €21m actually spent, and why the project extended over five years from conception to completion.

British architects Gaunt & Marnoch won the contract to design the new course in 2001. Partners Jonathan Gaunt and Steve Marnoch both spent extended periods on site, and the repeated master plans reflected their joint input. Later, though, Gaunt found himself tied to the golf project at Castleknock in Ireland (see GCA issue 6, p12), and so Marnoch took over as project architect. When the two partners went their separate ways in early 2006, the Zagaleta course became part of Marnoch's portfolio.

Talk now to Steve Marnoch and the mixture of joy and pain referenced above is only too clear. To build a golf course on so extreme a site is a major achievement for any architect. Marnoch, proud though he is of the Zagaleta course, recognises that much more could have been done.

And that, it's very clear, he finds incredibly frustrating.

Let's get a few things straight. This is a mountain golf course the like of which we have very few in Europe. A few statistics: the cost has been mentioned already. Earthmoving: over two million cubic metres of material. Scale: in many places there are alterations of original grade in excess of 40 metres. And inevitably the course is penal. Miss a fairway or a green and it's likely your ball is gone. Those are the facts of golf in this environment.

Marnoch has tried to make Los Barrancos as playable as possible. In places very narrow, he has incorporated width into the golf course wherever it could be done. When trying to build a fairway on a 45 degree sideslope, though, five yards of extra width means a vast extra amount of earthmoving. So in places the course is narrow. Don't buy property here if you are a chronic slicer: most of the holes seem to curve to the left, and in many cases a fade off the tee will be the wrong shot. A running draw, though, will often be rewarded. Three par fives in the first five holes might suggest an unbalanced routing.

But, as architect Marnoch says, in this environment one takes whatever the site gives. And if the first is something of a forced par five – the back tees were created post facto to add extra length, and the drive is fearfully intimidating for the first of the day – then both the fourth and fifth are terrific risk-reward holes, with opportunities to reach the green in two, but with disaster awaiting the inaccurate play.

One of the difficulties I find in evaluating Los Barrancos is that I have very little to compare it to. I have not seen the mountain golf courses of the western USA, and so it is hard for me to understand the state of the art. Another oddity is Marnoch's style. There are holes on Los Barrancos – the par three sixth is perhaps the best example – that could happily sit on a Scottish links. Now, it's not that this style is out of place in the mountain environment; it works very well. But pot bunkers and humpy-bumpy fairways are so far away from what one expects in the mountains that it's difficult to calibrate.

Another issue is the construction problems Marnoch and his site foreman Dan Ellwood battled with. The golf course was built by a local firm, and it is fair to say that the build was not carried out to the standards a mainstream golf contractor would have adhered to.

Shaping is an obvious example. In many fairways – the steeply downhill seventh is perhaps the most egregious example – the contractors have built drainage catch basins every few metres. Why one needs four drains within twenty metres on a slope so dramatic that surface drainage will be perfect is anyone's guess. The consequence is that the fairway appears to have dozens of small bomb craters in it. Fix this, and the golf course will dramatically be improved. To make the huge cuts and fills seem at least vaguely natural, the architect has tried to create rolls towards the edges of fairways, thus tying in the embankments. In places, such as the angled first fairway, this works well – creating, in this case, an opportunity for the golfer to use the contours to bounce his drive further down the hole. Elsewhere, though, there are many other such shapes that simply don't meld in as well as they might.

Similarly the standard of finishing is not as it should be. Marnoch has built many small pot bunkers, often extremely well placed to influence play. On a typical Scottish links, a tiny pothole bunker can dominate its surrounds, because the contours funnel balls into it, the short grass doesn't hold balls above ground, and the turf walls of the trap exact a severe penalty. Here the pot bunkers are cleverly located, but the lack of revetment and the shallowness of the traps – built with bulldozers because no trackhoe excavators were available – reduce the impact. If a pot bunker offers an easy escape its point is lost, and when it is more of a saucer than a pot, even more so.

Obtaining planning permission for Los Barrancos was a long and painful process.

The planned course routing was changed extensively and repeatedly, with the valley bottoms ruled out of bounds for construction on environmental grounds; this restriction created the need to hang fairways on steep hillsides, thus necessitating those vast quantities of earthmoving. Excess fill was used to create the practice ground; a tunnel was bored under the range to allow access to the clubhouse from the rest of the site.

These environmental constraints, combined with changing priorities in the development areas of the property, caused havoc for the golf course design.

Once version Z of the site masterplan had been reached, the architects decided not to continue producing updated plans, as the changes were too frequent. And the problems were not only on paper. The original seventeenth hole, a par three playing over a ravine from a high tee to a green cut out of the mountainside, is now buried under thousands of tonnes of rock as a result of a huge landslide. The loss of this hole – mourned especially by Marnoch who felt it was the best one shotter on the course – has resulted in the club crudely chopping the interesting risk-reward par five fifteenth into two, and has also forced the creation of a new tee for the home hole. None of these compromises are satisfactory, and Marnoch is in discussions with his client as to possible routes forward.

Standout holes on the Barrancos course include the par three second, which at first glance appears to be a fairly standard pond hole. But the large green features a terrific pin position atop a severe ledge to the back left. To get a tee ball close to this flag will require tremendous skill, especially since the chip back, in the event of going long, will not be for the faint hearted. The third hole, a short, sharp uphill par four, offers the bold player a chance to drive the green, but the carry, over a huge drop, looked extremely intimidating to me. Marnoch assured me it had been achieved on a number of occasions, but I'm not so sure! The par four eleventh hole, though, is my favourite on the golf course. Death awaits the golfer who pushes his tee shot off the right edge of the fairway, but a deep bunker to the front left of the green makes that side hugely preferable, especially if the flag is set left. From the left, the bunker blinds most of the green; from the right, the golfer has a reasonable view of his target. It is classic strategic golf, and a very attractive hole.

To say that the Zagaleta course is not without its flaws would be something of an understatement. Yet both Marnoch and his former partner Gaunt look at the project with some considerable pride, and they are right to do so. Simply building a golf course on such an extreme site is a major achievement, and when one factors in the extraneous problems of permitting, environmental restrictions, contractors, landslides et al, it is hard to imagine how the course ever happened.

That, for all the obvious flaws, there is a spectacular and mostly playable course there is quite amazing.

This article first appeared in issue 7 of GCA, published January 2007