The maps they inherited from when Iron Council was the TRT train became useful again. The perpetual train was still embedded in the loosest ink, the crosshatched beige that indicated uncertainty, but eastward the drawings grew more clear; stippling of brush, the watercolour wash of fen, contours of hills in precise line. This was not land on which tracks had been laid, but it was in the city’s ken. The Council could track its route through the ink.

They checked and rechecked. It was a burgeoning revelation. They were heady and astounded. "Around the long lake here. We’ve Cobsea to our south. We should avoid them, get northside of the lake as fast we can. We’ll bring Council justice to New Crobuzon."

Even knowing the militia followed them could not cow them. "They’ve come after us. They followed us into the stain," Judah told Cutter. "They’ve triggered a golem trap I put in the cacotopos." No militia had ever gone so deep. This must be a dedicated squad, who realised the Council was heading back for New Crobuzon.

"We’ll go close to the hills." Days ahead, a backbone of mountains rose and extended half a thousand miles to New Crobuzon. "We’ll skirt them; we’ll take the train through the foothills. To New Crobuzon."

There were still months to go, but they went fast. Scouts went to see where bridges or fording were needed, where swampers had to fill wetland, where tunnellers and geothaumaturges would carve out passages. History felt quicker.

Drogon the whispersmith was alight with excitement, sounding in Cutter’s ears, telling him he could not believe that they had come through, that they had achieved this, that they were so close to being home. "Got to clock what we done," he said. "Got to mark it. No one’s ever done this, and plenty’ve tried. There’s still a way to go, and it’s still land no one knows well, but we’ll do it."

Judah sat on the traintop and watched this suddenly unalien landscape. "It ain’t safe," he told Cutter. "Can’t say it’s safe at all." He spent much time alone, listened to his voxiterator.

"Judah, Cutter," Elsie said, "we should go back to the city."

She was silent in these days, with Pomeroy’s death. She had found a calm that let her live in her loneliness. "We don’t know what’s happening there; we don’t know what state they’re in. We need to get them word that we’re coming. We could sway things. We could change it."

It was a long way still, and there were many things that stood to stop them.

"She’s right." Drogon spoke to each of them. "We need to know."

"It ain’t no matter, I don’t think," Judah said. "We’ll go, nearer the time. We’ll go and get a welcome ready, prepare for them."