This set of plans on Archnet is a complete set of the Plan d'Assurance de Constantinople (Insurance Plan of Constantinople), issued by Charles E. Goad, a London-based civil engineer, in three volumes between 1904-1906. The fire insurance maps show building footprints, usages, and materials in the city of Istanbul.
Volume I, Stamboul, was published in September 1904. It included sheets 1-20 at 1/600 scale, with a key map, index sheet, and "Explanation of Signs" sheet.
Volume II, Pera & Galata, was published in December 1905. It included sheets 24-30 & 35-45 at 1/600 scale, with a key map and two index sheets.
Volume III, Kadi-Keui, was published in April 1906. It included sheets 51-64 at a 1/1,200 scale, with a key map and index sheet.
Individual sheets can be downloaded from the list below.