The Swallows are back at the lake for another summer of sailing, camping, exploration, and adventure. John, Susan, Titty, and Roger Walker return eagerly to Wild Cat Island and their friends Nancy and Peggy Blackett, the Amazon pirates. But their plans are overturned when Swallow strikes Pike Rock and sinks. With their boat needing repairs and Wild Cat Island temporarily out of reach, the children turn inland, where they discover a secluded valley on the moors and make it their new camp-Swallowdale. Their new headquarters opens the way to trout fishing, caves, expeditions across the fells, and an ambitious climb of the mountain they call Kanchenjunga. Meanwhile, Nancy and Peggy must contend with the formidable Great Aunt Maria, whose ideas about proper behavior make joining the adventures considerably more difficult. Filled with sailing, camping, friendship, discovery, and the pleasures of independence, Swallowdale expands the world of Swallows and Amazons into an unforgettable summer in the English lake country.