Greensburg is a city in, and the county seat of, Kiowa County, Kansas, United States. As of the 2020 United States census, the population of the city was 740. It is home to the world's largest hand-dug well. On the evening of May 4, 2007, Greensburg was devastated by an EF5 tornado that leveled at least 95 percent of the city, killing eleven people between the ages of 46 and 84. The town had a population of 2,000 people in the late 1990s, and 1,400 people before the tornado leveled the town.