Abandoned 1931 Illinois National Guard armory in Cairo (pronounced CARE-o), Illinois, a small city at the southern tip of the state, wedged between Kentucky and Missouri. Once a booming river town of 15,000 population in the early 20th Century, Cairo declined into what some call a ghost town one-fifth the population a century later following several racially tinged riots and severe flooding, including one in 2011 in which the entire city was evacuated. Photo by Carol Highsmith, 2019.