The trip from the Socket into Sheffield proper was by subway, but Art would have been too miserable to notice a view even if there had been one. Wasted and unsteady, he tiptoed bouncily down a tall hallway after someone from Praxis, and collapsed thankfully on a bed in a small room. Martian g felt blessedly solid when he was lying down, and after a while he fell asleep.

When he woke he could not remember where he was. He looked around the little room, completely disoriented, wondering where Sharon had gone and why their bedroom had gotten so small. Then it came back. He was on Mars.

He groaned and sat up. He felt hot and yet detached from his body, and everything was pulsing slightly, though the room lights appeared to be functioning normally. There were drapes covering the wall opposite the door, and he stood and walked over, and opened them with a single pull.

“Hey!” he cried, leaping back. He woke up a second time, or so it felt.

It was like the view out an airplane window. Endless open space, a bruise-colored sky, the sun like a blob of lava; and there far below stretched a flat rocky plain — flat and round, as it lay at the bottom of an enormous circular cliff — extremely circular, remarkably circular, in fact, for a natural feature. It was difficult to estimate how distant the far side of the cliff was. Features of the cliff were perfectly clear, but structures on the opposite rim were teensy; what looked like an observatory could have fit on a pin-head.

This, he concluded, was the caldera of Pavonis Mons. They had landed at Sheffield, so really there could be no doubt about it. Therefore it was some sixty kilometers across the circle to that observatory, as Art recalled from his video documentaries, and five kilometers to the floor. And all of it completely empty, rocky, untouched, primordial — the volcanic rock as bare as if cooled the week before — nothing at all of humanity in it — no sign of terra-forming. It must have looked exactly like this to John Boone, a half century before. And so … alien. And frig. Art had looked into the calderas of Etna and Vesuvius, while on vacation from Tehran, and those two craters were big by Terran standards, but you could have lost a thousand of them in this, this thing, this hole…

He closed the drapes and got slowly dressed, his mouth imitating the shape of the unearthly caldera.

A friendly Praxis guide named Adrienne, tall enough to be a Martian native but possessing a strong Australian accent, collected him and took him and half a dozen other new arrivals on a tour of the town. Their rooms turned out to be on the city’s lowest level, though it wouldn’t be lowest for long; Sheffield was in the process of burrowing downward these days, to give as many rooms as possible the view onto the caldera that had so disconcerted Art.

An elevator took them up nearly fifty stories, and let them out in the lobby of a shiny new office building. They walked out its big revolving doors and emerged on a wide grassy boulevard, and walked down it past squat buildings faced with polished stone and big windows, separated by narrow grassy side streets, and a great number of construction sites, as many buildings were still in various stages of completion. It was going to be a handsome town, the buildings mostly three and four stories tall, getting taller as they moved south, away from the caldera rim. The green streets were crowded with people, and the occasional small tram running on narrow tracks set in the grass; there was a general air of bustle and excitement, caused no doubt by the arrival of the new elevator. A boom town.

The first place Adrienne took them was across a boulevard to the caldera rim. She led the seven newcomers out into a thin curving park, to the nearly invisible tenting that encased the town. The transparent fabrics were held in place by equally transparent geodesic struts, anchored in a chest-high perimeter wall. “The tenting has to be stronger than usual up here on Pavonis,” Adrienne told them, “because the atmosphere outside is still extremely thin. It’ll always be thinner than the lowlands, by a factor of ten.”

She led them out into a viewing blister in the tent wall and, looking down between their feet, they could see through the blister’s transparent deck, straight down onto the caldera floor some five kilometers below them. People exclaimed in delicious fright, and Art bounced on the clear floor uneasily. The width of the caldera was coming into perspective for him; the north rim was just about as far away as Mount Tamalpais and the Napa hills when one descended into the San Jose airport. That was no extraordinary distance. But the depth below, the depth; over five kilometers, or about twenty thousand feet. “Quite a hole!” Adrienne said.

Mounted telescopes and display plaques with map drawings enabled them to spot the previous version of Sheffield, now lying on the caldera floor. Art had been wrong about the caldera’s untouched primeval nature; an insignificant pile of cliff-bottom talus, with some shiny dots in it, was in fact the ruins of the original city.

Adrienne described with great gusto the destruction of the town in 2061. The falling elevator cable had, of course, crushed the suburbs east of its socket in the very first moments of the fall. But then the cable had wrapped all the way around the planet, delivering a massive second blow to the south side of town, a blow which had caused an undiscovered fault in the basalt rim to give way. About a third of the town had been on the wrong side of this fault, and had fallen the five kilometers to the caldera floor. The remaining two-thirds of the town had been knocked flat. Luckily the occupants had mostly evacuated in the four hours between the detachment of Clarke and the second coming of the cable, so loss of life had been minimized. But Sheffield had been utterly destroyed.

For many years after that, Adrienne told them, the site had lain abandoned, a wreck like so many other towns after the unrest of ‘61. Most of those other towns had been left in ruins, but Sheffield’s location remained the ideal place for tethering a space elevator, and when Subarashii began organizing the in-space construction of a new one in the late 2080s, construction on the ground had rapidly followed. A detailed areological investigation had found no other faults in the southern rim, which had justified rebuilding right on the edge, on the same site as before. Demolition vehicles had cleared the wreckage of the old town, shoving most of it over the rim, and leaving only the easternmost section of town, around the old socket, as a kind of monument to the disaster — also as the central element of a little tourist industry, which had clearly been an important part of the town’s income in the fallow years before an elevator had been reinstalled.

Adrienne’s next point on the tour led them out to see this preserved bit of history. They took a tram to a gate in the east wall of the tent, and then walked through a clear tube into a smaller tent, which covered the blasted ruins, the concrete mass of the old cable facility, and the lower end of the fallen cable. They walked a roped path that had been cleared of wreckage, staring curiously at the foundations and twisted pipes. It looked like the results of saturation bombing.

They came to a halt under the butt end of the cable, and Art observed it with professional interest. The big cylinder of black carbon filaments looked nearly undamaged by the fall, although admittedly this was the part that had hit Mars with the least force. The end had jammed down into the Socket’s big concrete bunker, Adrienne said, then been dragged a couple of kilometers as the cable had fallen down the eastern slope of Pavonis. That wasn’t that much of a beating for material designed to withstand the pull of an asteroid swinging beyond the areosynchronous point.