The Boat Of A Million Years by Poul Anderson

A sweeping, multi-millennial saga that follows a small group of naturally immortal humans born at different times who live through ancient civilizations, modern upheavals, and future spacefaring eras; as they repeatedly face love, loss, exile, and changing moral and cultural landscapes, they wrestle with loneliness, purpose, and the ethics of eternity, eventually taking part in humanity’s expansion and confronting profound choices about identity, belonging, and what it means to move beyond the limits of ordinary life.

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