Dark Earth / Rebecca Stott.

In Dark Ages Britain, sisters Isla and Blue live in the shadows of the Ghost City, the abandoned ruins of the once-glorious, mile-wide Roman settlement Londinium on the north bank of the Thames. The native Britons and the new migrants from the East who scratch out a living in small wooden camps in its hinterland fear that the crumbling stone ruins are haunted by vengeful spirits. But the small island they call home is also a place of exile for Isla, Blue, and their father, a legendary blacksmith accused of using dark magic to make his firetongue swords. The local warlord, Osric, has put the Great Smith under close guard and ruled that he make his magnificent swords only for him so that he can use them to build alliances and extend his kingdom. For years, the sisters have been running wild, Blue communing with animals and plants and Isla secretly learning her father’s trade, which is forbidden to women. But when their father suddenly dies, they find themselves facing enslavement by Osric and his cruel, power-hungry son Vort. Their only option is to escape to the Ghost City, where they discover an underworld of rebel women living secretly amid the ruins. As Blue and Isla settle into their new life, they find both refuge and community with the women around them. But it is all too fragile. With the ruins collapsing all around them, Blue and Isla realize they can’t elude the men who hunt them forever. If they are to survive, they will need to use all their skill and ingenuity—as well as the magic of their foremothers—to fight back.