The cliffs behind him were rosy with the same light, the sand beneath his soles strewn with shadows like wavelets. The air smelled of salt.
He felt something he had not felt for a long time, and it took a while before he admitted to himself that it was fear. He shrugged, hoisted his pack over his shoulder and continued on towards the distant tower, leaving a deep, scuffed trail of footprints behind him in the talc-fine sand. A vague, gauzy cloud of accompanying dust hung in the air.
It was the ten thousand, two hundred and seventh day of his time in the crypt. He had been here for almost twenty-eight years. Outside, in the other world, a little more than a day had passed.
The wall was obsidian; pitted in places, still highly polished in others. It met the sands and plunged into them like a black knife a kilometre long and fifty metres high at least. He stood in the silence, staring up at the almost featureless cliff, then trod down to the nearest shore. The wall extended a hundred metres or so out to sea. He turned on his heel and set off for the other end.
It was the same. He squatted by the shore and tested the water as a wave broke and rolled, pushing foam up the slope of sand. It was warm. He’d have to swim. He’d thought he might.
He started to undress.
He had not ever paid very much attention to his geographical position in the crypt, though it did roughly correspond to hardware in the base-level world. He supposed he must have wandered over much of South and North America before he had encountered the tonsured woman with her elaborately coded message; that had been, as nearly as he could make out, in a position which equated to somewhere in the North American Midwest; Iowa or Nebraska, he thought. His path since then had led him through Canada, Greenland, Iceland, Britain, Europe and Asia Minor to Arabia.
The sea crossings had been the most dangerous parts of his journey; whether they were effected by the likeness of a bridge or a tunnel, they represented choke points for travellers, and such a focusing of potential prey had in most cases produced a predatory exaggeration of the level’s ecological balance. He had had to use the sword a few times, and – on occasion – opponents had attempted to best him through other levels of the crypt, imagining him into situations within which they thought he could more easily be defeated and absorbed.
He found, however, that he had little difficulty in assuming control in such situations. Much appeared to depend on one’s wit; a general flexibility and quickness of mind plus an extensive and catholic knowledge-base – as long as these attributes were combined with a generous dash of ruthlessness – were all that one really needed to operate successfully within such imagined realities.
He had walked over broad bridges and within great tunnels hundreds upon hundreds of kilometres long, travelling within the spaces afforded by the slow sweeps of the writhing data highways, in something like a trance sometimes when the pace was forced and he could not afford to sleep, imagining himself to be a molecule of water trapped within the fold of some Archimedean Screw, a wave carried upon some articulation of light within a subsea cable, a fleck of sand-dust borne on the dark gurglings of a submerged water course veined beneath the baking desert.
He swam round the wall, at first attempting to keep his pack balanced on his head, then, when the waves became too rough, resorting to pushing it before him.
The waves mounted, the wind increased, and he realised that he was being blown away from the shore and the wall. He swam on as best he could but after swallowing water and being continually overwhelmed he was finally forced to surrender his heavy, waterlogged pack and all it contained to the sea; it sank quickly. He struck out with all his remaining strength for the just-glimpsed beach beyond the surf-skirted blackness of the wall.
Only his dreams had disturbed him on his journey to this place, still nagging at him with their images of slow eclipses and the death of stars all glimpsed above impressions of battle.
As he’d neared what he still only guessed and hoped was his goal, the dreams had begun to change, and instead of pan-historical images of the Encroachment, he had started to experience what appeared to be presentiments of its effects.
He’d seen the night sky, utterly black but for a twice-dimmed moon. He’d seen a cloudless day that was nevertheless dim, and a sun shining within that faded clarity that was high and full and yet dull orange, not fiery yellow-white; a sun it was possible to gaze at comfortably with the naked eye.
In his dreams he’d seen the weather change and the plants die, and later the people.
By virtue of its location Serehfa did not have a four-season year, alternating between seasons of dry and wet heat whose external effects were moderated by the construction’s altitude as well as the carefully altered geography of its surroundings, but he remembered the spring and later the summer coming to Seattle and to Kuybyshev in the year that he had left base-reality behind, and in his dreams that summer did not last as long as the one before, and winter came earlier. The pattern was repeated more intensely in the southern hemisphere.
The following winter lasted throughout the spring before finally delivering a summer hardly warmer than the autumn it quickly lapsed into, and after that there was nothing but winter; winter with the dim face of thee sun high in the sky, or a winter set within a winter when the sun dipped nearer the horizon.
The pack ice grew continually, permafrost buckled the ground and thrust blisters of ice through what had been temperate soils, the currents of the air and of the sea changed as lakes and rivers froze and the hearts of the continents and the upper levels of the oceans cooled.
Plants died back, creating new deserts where vegetation used to copious heat and light had withered and plants better suited to the colder conditions had not yet had time to colonise, while those plants themselves succumbed to the sudden, smothering weight of the advancing snow and ice.
Animals of all descriptions found themselves being concentrated in a smaller and smaller band around the waist of the world, raising the contest to survive to new levels of ferocity, while even in the comparative warmth of the oceans life became gradually less abundant as the white shutters of freezing sea irised. slowly closed over the brash-ice waves, and the trickling streams of sunlight energising the top of the food chain were reduced almost to nothing.
As though in mocking compensation for the shaded sun, great storms of light played about the heavens at night, flickering like aurorae, cold and vast, inhuman and numbing.
Still in those dreams he saw people crouched round fires, struggling through snow drifts with packs and possessions, taking refuge in mines and tunnels as the snow piled and the glaciers advanced and the icebergs crunched aground off equatorial shores and the pack ice spread from either pole like crystals in some drying solution.
No spears of fire or engines of more sophisticated energies lifted exiles into space, but for all the corpses abandoned at roadsides, for all the men, women and children left to die or freezing together in cars, carriages, houses, villages, towns and cities, still people persevered; retreating, stocking up, burrowing down, sealing up.
The fastness that had been Serehfa fell slowly, surrendering to aggregated megatonnes of ice until only the fast-tower itself remained, a listing cenotaph to human hubris. Then the glaciers swept down from the mountains to north and south and scoured even that from the surface of the world; the fast-tower’s only memorial was a brief volcanic eruption wrenched from the earth by the thermonuclear-level energies its final fall created.
And so humanity left the surface of the world to the ice, wind and snow, and sheltered, reduced and impoverished, within the stony depths of the planet’s skin, finally coming to resemble nothing more than parasites in the cooling pelt of some huge dying animal.
With it it took all its knowledge of the universe and all the memories of its achievements and all the coded information defining the animals and plants that had survived the vicissitudes of time and evolution and – especially – the pressure of the human species’ own until then remorseless rise.
Those buried citadels became whole small worlds of refugee communities and spawned still smaller worlds as new machines took over the job of maintaining the levels of the crypt, until gradually more and more of what was in any sense humanity came to reside not simply in the created world of its tunnels, caverns and shafts but within those worlds in the generated realities produced by its computers.