The stolen lake - Joan Aiken

Dido Twite, heroine of Black Hearts in Battersea and Nightbirds on Nantucket, is on her wildest adventure yet. On her way back to London aboard the Thrush, Dido and crew are summoned to the aid of the tyrannical queen of New Cumbria. Her island is an infernal place where birds carry off men and fish eat human flesh. The queen is greatly distressed because a neighbouring king has stolen her lake. Dido faces fire, flood, wild beasts and, ultimately, threat of execution in order to get the lake back. Is she equal to the challenge?

A rich mixture of legend, fantasy, humour and pure snowballing adventure.