Coit Tower and Alcatraz view of San Francisco. Original image from Carol M. Highsmith’s America. Digitally enhanced by… https://www.rawpixel.com/image/2110356/carol-highsmiths-californiaFree Image from public domain licenseAlcatraz Island is located in San Francisco Bay, 1.25 miles (2.01 km) offshore from San Francisco, California, United States. https://www.rawpixel.com/image/4022891/photo-image-ocean-bird-natureFree Image from public domain licenseGezicht op de Montfoortse Toren te Veere (in or before 1696) by anonymous https://www.rawpixel.com/image/13776944/gezicht-montfoortse-toren-veere-in-before-1696-anonymousFree Image from public domain licenseKuching, Sarawak: a square-towered building and the jail. Photograph. https://www.rawpixel.com/image/13998544/kuching-sarawak-square-towered-building-and-the-jail-photographFree Image from public domain licenseKoninklijke gevangenis te Madrid (1694 - 1737) by Pieter van den Berge, Pieter van den Berge, Staten van Holland en West… https://www.rawpixel.com/image/13748634/image-paper-horse-cartoonFree Image from public domain license