The library of Casa Lajolo consists of two different collections. One is the Chialamberto-Lajolo collection, and the other is the De Vecchi collection, from the Milan part of the family. There are about 1600 volumes in the library. The oldest completed section in the Chialamberto-Lajolo libraries is from the year 1610. In the De Vecchi library, the oldest piece dates back to 1701(a copy of Cicero’s Orations).
The Chialamberto-Lajolo collection is special because it has never been moved from its premises. It reflects the life events of the family and its successors and contains interesting notes of possession. The oldest book is a memoir about the life of San Carlo Borromeo, who was the archbishop of Milan. It was written in 1610. However, the most important pieces of the collection are two volumes about the history of the two branches of the family. The first one is “Historical-Diplomatic Monuments of the Ferrero-Ponziglione Archives and Other Noble Subalpine Houses” by Giovanni Battista. It was published by Ribotta in Turin in 1858 and is dedicated to the noble cavalry officer Ferdinando Laiolo by the author on 1 July 1858. On page 661, there is a narration of the deeds and events in the life of Domenico Simone Ambrosio di Chialamberto.