Wikipedia
Orbitsville
Orbitsville (ISBN 0-330-25013-2), published in book form in 1975, is a science fiction novel by Bob Shaw about the discovery of a Dyson sphere-like artefact surrounding a star.
The novel had previously appeared in three instalments in Galaxy Science Fiction, in June, July and August 1974. After its publication as a book it won the British Science Fiction Award for the best novel in 1976.
Shaw wrote two sequels, Orbitsville Departure (ISBN 0-671-69831-1), published in 1983, and Orbitsville Judgement, published in 1990.