Plain City is a city in Weber County, Utah, United States. The population was 5,476 at the 2010 census. It is part of the Ogden–Clearfield, Uta…Plain City is a city in Weber County, Utah, United States. The population was 5,476 at the 2010 census. It is part of the Ogden–Clearfield, Utah Metropolitan Statistical Area. The Salt Lake Valley settlement began when wagon trains of members of the Church of Jesus Christ of Latter-day Saints began arriving in 1847. By 1858, farmers from the then-settled towns of Lehi and Kay's Creek, looking for a new place to homestead, began considering the area now known as Plain City. On 17 March 1859, led by Lorin Farr, a group arrived to begin homesteading. Soon after arriving, the group surveyed a townsite and assigned building lots. The town layout used an organized grid system of blocks and streets, originally six blocks north-to-south and three blocks east-to-west. Each block was 5 acres in area, divided into 4 lots. The first settlers were allowed their choice in the selection of a lot.