Would you like a list of similar post-apocalyptic novels from Spanish or Catalan literature instead?
Because the book is still under copyright (Manuel de Pedrolo died in 1990, so his works remain protected in Spain and the EU for 70 years after his death), you cannot legally download a free PDF from public sites.
Their journey takes them across a depopulated Europe and Africa, gathering resources, learning from surviving books and manuals, and eventually realizing that their greatest responsibility is to repopulate the planet and rebuild human civilization. The "second origin" of the title refers to the new humanity that will rise from their efforts.