Inhabiting new country is always a challenge. As soon as the tenting of Nirgal Vallis was done, Séparation de L’Atmosphère set up some of their largest mersocosm aerators, and soon the tent was filled with 500 millibars of a nitrogen-oxygen-argon mix that had been pulled and filtered out of the ambient air, now at 240 millibars. And the settlers started moving in, from Cairo and Senzeni Na, and everywhere else on the two worlds.

First people lived in mobile trailers, next to small portable greenhouses, and while they worked on the soils of the canyon with bacteria and plows, they used the greenhouses to grow their starter crops, and the trees and bamboo they would use to build their houses, and the desert plants they would spread outside the farms. The smectite clays on the canyon floor were a very good base for a soil, though they had to add biota, nitrogen, potassium— there was plenty of phosphorus, and more salts than they wanted, as usual.

So they spent their days augmenting the soil, and growing greenhouse crops, and planting hardy salt-desert plants. They traded all up and down the valley, and little market hamlets sprang up almost the day people moved in, as well as trails between homesteads, and a trunk road running down the middle of the valley, next to the stream. Nirgal Vallis had no aquifer at its head, and so a pipeline from Marineris pumped enough water to the head to start a small stream running. Its waters were collected at the Uzboi Gate and piped back up to the top of the tent again.

The homesteads were about half a hectare each, and almost everyone was trying to grow the bulk of their food on that space. Most divided their land up into six miniature fields, rotating crops and pasturage each season. Everyone had their own theories of cropping and soil augmentation. Most people grew a small cash crop, nuts or fruits or lumber trees. Many kept chickens, some kept sheep, goats, pigs, cows. The cows were almost all miniatures, no bigger than pigs.

They tried to keep the farms down on the canyon floor by the stream, leaving the higher rougher ground under the canyon walls to wild land. They introduced an American Southwest community of desert animals, so that lizards and turtles and jackrabbits began to live nearby, and coyotes, bobcats, and hawks to make depredations among their chickens and sheep. They had an infestation of alligator lizards, then one of toads. Populations slowly settled into their sizes, but there were frequent sharp fluctuations. The plants began to spread on their own. The land began to look as if its life belonged there. The redrock walls stood unchanged, sheer and craggy over the new riverine world.