There might be more than you want to know about Martian topography and geology, but it's a brilliant conclusion to this epic trilogy. It's the story of people as much as science and what happens over generations.
Sabishii was located on the western side of a five kilometre high prominence called the Tyrrhena Massif, south of Jarry-Desloges Crater, in the ancient highlands between Isidis and Hellas, centred at longitude 275 degrees, latitude 15 degrees south. A reasonable choice for a tent town site, as it had long views to the west, and low hills backing it to the east, like moors. But when it came to living in the open air, or growing plants out in the rocky countryside, it was a bit high; in fact it was, if you excluded the very much larger bulges of Tharsis and Elysium, the highest region on Mars, a kind of bioregion island, which the Sabisiians had been cultivating for decades.