The story is set partially in the contemporary world of England and partially in the world of Lyndesfarne. In Lyndesfarne, all but the simplest technology does not work, but a sophisticated society functions using pervasive magic. The crossing between the worlds is formed by two stone causeways across the marshes, joined by the Old Bridge; its immense masonry arches are partially reinforced by steel alloys and by magical sprites, visible as orange sparks inside the stonework itself. A short section in the middle of the central arch, in the region where neither engineering nor magic is entirely reliable, requires both metal and magical enhancement ...
Excerpt:
The old bridge to Lyndesfarne was an engineering marvel of its time. Unfortunately, its time was now several hundred years in the past. This caused any number of problems, not least of which was the fact that any kind of travel over the bridge almost invariably took ages.
Kevin stood on a windswept hillock, looking towards the ancient stone causeway which strode out to the arches of the bridge. The view across the sea channel was hazy, as always. Even on a bright spring morning, something mysterious about the boundaries of Lyndesfarne meant that it was only vaguely possible to make out features on what Kevin persisted in thinking of as the Island.
At this late morning hour, traffic on the crossing was relatively heavy. A fair number of people on foot, of course, since this was the most reliable way to travel. Wheeled transportation consisted of horse-drawn wagons and caravans of incongruously old-fashioned design, all heavy woodwork and canvas. The low-tech style meant that they could be relied upon to work on either side of the crossing. The bridge itself was only wide enough for a single vehicle, so there was often a queue of impatient horses and people on the causeway.
Motorised or magical transport on the causeway and bridge was rigorously, if discretely, discouraged by the Guardians on either side, but every now and then something slipped through. Even as Kevin watched, a wagon of suspiciously lightweight design heading towards the Island grated to a halt just after the apex of the central arch. All four wheels had suddenly jammed with a screech of iron tyres on stone. Groans and curses from the carters on either side could be heard over the wind, even from this distance.
"What an idiot!" muttered Kevin to himself, "He's probably using wheel bearings salvaged from a car."
Simply put, anything but the most basic technology did not work on Lyndesfarne. Anything electrical failed immediately; usually, but not always, it would start working again - sometimes erratically - when returned to the Mainland. Hardened metal alloys softened and bent, clockwork stopped, plastics became brittle and cracked. Kevin had been advised to leave his laptop computer, mobile phone and wristwatch in the boot of his car every time he went to cross to the Island. This was good advice, Kevin thought, and worth paying
attention to. It was all too easy to leave some item in a pocket, only to later discover that it was either broken or functioned erratically.
After all these months, Kevin was beginning to understand the depth of the centuries-old misinformation campaign about Lyndesfarne. Sure, he had heard of the place, in a vague kind of way, before he had joined the New Bridge team. His first reaction had been, it seemed in hindsight, much like those of his colleagues when he occasionally ran into them in the Manchester office.
"Lyndesfarne? Oh, that's that little island up north somewhere.
Hard to get to. Gets cut off by the tide, doesn't it?"
"Supposed to be something mystical about it, isn't there? Full of hippies, or New Age travellers, isn't it?"
"Never been there myself. Sounds kind of dull to me." "Why do they want a bridge, anyway?"
Lyndesfarne was indeed shown on maps of North East England as a small and uninhabited island. The maps, and indeed the view from the Mainland coast, showed an almost bare island, with just a few windswept trees, many rocky crags and promontories, and large areas of rough grasses and sand-dunes. There was no apparent habitation and no obvious signs of cultivation, just a few suggestions of some shore-side ruins from a bygone age, although it was not immediately clear whether they were fortifications, or religious in origin.
But there was a road, and a causeway, and a bridge. And when you crossed the bridge, you discovered the deception. From the other side, Lyndesfarne was a whole world - a world in which the scientific and engineering laws, those laws which had been so elaborately and expensively drummed into Kevin's head at school and at university, simply did not apply. It was a world as large and complex as Kevin's own, with its own rich and sophisticated way of getting things done; a world with its own history, and cultures, and languages; a world which, for want of a better word, ran on magic.
From Lyndesfarne, the Mainland of Kevin's world appeared as an island. Lyndesfarne maps showed a different, but equally uninspiring representation, and the view from the other end of the causeway was that of a heavily wooded island, with a few rocky outcrops visible amongst the trees. Again, no cultivation and no habitation.