Wheelworld — Harry Harrison

TOO DANGEROUS TO LIVE. TOO VALUABLE TO KILL.

Jan Kulozik is in exile: sentenced to service the machines of Halvork, the farmworld that grows crops to fill the holds of Earth's grain-ships. This Wheelworld, baked by eternal summer, is a world of peasants enslaved by a handful of powerful families.

Then disaster. One year the ships do not come; starvation threatens Halvmork. Jan rallies the people for their own survival, and guides them on a perilous trek across half a planet. Battling heat and savage creatures, earthquakes and volcanoes, fighting the violence and treachery of the Families, Jan leads the people of Wheelworld to their new destiny.