There are 42 books in Railway Series by W. Awdry and there are 2 ancillary books in related to this series .
The Railway Series, or the Thomas the Tank Engine series, is a set of story books about a railway system located on the fictional Island of Sodor. There are 42 books in the series, the first being published in 1945. Twenty-six were written by the Rev. Wilbert Awdry, up to 1972.
Other series related to Railway Series by W. Awdry are Thomas and Friends and Thomas Story Library .