Malcolm Metcalf, a man from Gorleston, has visited every library in Norfolk, a total of 48 libraries, which he described as a "privilege".
He praised the librarians for their warm welcomes and refreshments, and also visited specialized libraries such as Gresham's College and Norwich Cathedral Library.
A "privilege" - Malcolm Metcalf on visiting every library in Norfolk
His next challenge is a mammoth jigsaw puzzle sale at the Shrublands Youth and Adult Centre on October 25.
Author's summary: Malcolm Metcalf completes 90 challenges in his 90th year.