Julia Blackburn has always collected things that hold stories about the past, especially the very distant past: mammoth bones, little shells that happen to be two million years old, a flint shaped as a weapon long ago. Shortly after her husband’s death, Blackburn became fascinated with Doggerland, the stretch of land that once connected Great Britain to Continental Europe but is now subsumed by the North Sea. She was driven to explore the lives of the people who lived there—studying its fossil record, as well as human artifacts that have been unearthed near the area.

In Time Song, Blackburn brings us along on her journey to discover what Doggerland left behind, introducing us to the paleontologists, archaeologists, fishermen and fellow Doggerland enthusiasts she meets along the way. She sees the footprints of early humans fossilized in the soft mud of an estuary alongside the scattered pockmarks made by rain falling eight thousand years ago. She visits a cave where the remnants of a Neanderthal meal have turned to stone. In Denmark she sits beside Tollund Man, who seems to be about to wake from a dream, even though he had lain in a peat bog since the start of the Iron Age.

As Doggerland begins to come into focus, what emerges is a profound meditation on time, a sense of infinity as going backward and an intimation of the immensity of everything that has already passed through its time on earth and disappeared.