Second paragraph of third section:
Dann had wanted to leave the Centre – leave the past – because of the weight of sorrow on him, which he believed he understood. It was natural. Of course he was bereft, but he would get over it. He had no intention of subsiding into unhappiness. No, when he got walking, really moving, he would be better. But he had not got into his stride, his rhythm: it was what he needed, the effortlessness of it, when legs and body were in the swing of the moment, a time different from what ruled ordinary sitting, lying, moving about – never tiring. A drug it was, he supposed, to walk like that, walking at its best, as he had done sometimes with Mara, when they were into their stride.
I hadn't realised while reading that this was a sequel to a book I haven't read, Mara and Dann, so was judging it more on its own merits. (People who have read Mara and Dann generally seem to think that it was better.)
The setting is a post-apocalyptic world where Europe is covered by melting ice sheets, the Mediterranean has dried up but slowly starting to fill again, and the remnants of humanity are trying to hold onto and maybe rebuild civilisation. Dann is thrust into a leadership role despite his bad health, and, surrounded by his companions of the title, is drawn into a quest to save a library of knowledge from the old days. The prose is terse, but the setting and the characters conveyed effectively, Dann's personal drama very closely linked to the question of what will happen to the cultural heritage now under threat from the changing climate. It's also fairly short. You can get it here.
This was the top unread book on my shelves acquired in 2011. Next on that list is The God Instinct: The Psychology of Souls, Destiny and the Meaning of Life by Jesse Bering.