Martello Towers Near Bexhill, Sussex, plate 34 from Liber Studiorum by Joseph Mallord William Turner https://www.rawpixel.com/image/8990333/image-paper-cloud-frameFree Image from public domain licenseMartello Towers near Bexhill, Sussex by Joseph Mallord William Turner https://www.rawpixel.com/image/8988470/martello-towers-near-bexhill-sussex-joseph-mallord-william-turnerFree Image from public domain licenseMichael Johnson at Martello Tower, Guernsey by Eric Lee Johnson. https://www.rawpixel.com/image/13031150/michael-johnson-martello-tower-guernsey-eric-lee-johnsonFree Image from public domain licenseSham Fight by New South Wales Government Printing Office https://www.rawpixel.com/image/14322310/sham-fight-new-south-wales-government-printing-officeFree Image from public domain licenseMartello Tower,Tybee Island, Georgia, Built in 1537, by the Spanish by Henry P Moore https://www.rawpixel.com/image/14273340/photo-image-person-public-domain-towerFree Image from public domain licenseEast Martello Tower. Old Spanish fort, Key West, Florida. Sourced from the Library of Congress. https://www.rawpixel.com/image/12273484/photo-image-plant-sky-public-domainFree Image from public domain license