Sheldon is a city in O'Brien and Sioux Counties in the U.S. state of Iowa, along the Floyd River. it is the largest city in O'Brien County. According to the United States Census Bureau, the city has a total area of 4.4 square miles (11.4 Square Kilometer).None of the area is covered with water. Sheldon was founded in 1872 and named after the railroad man Israel Sheldon. It was early a strategic location on the rail for businesses from as far away as Minneapolis and Omaha. Today, the city is at the crossroads of Iowa Highway 60 and U.S. Highway 18. In 1961, the city made headlines when it was revealed that Burnice Geiger had embezzled more than two million dollars from her father's bank.