Allen, or Allen City, is a Floyd county town about four miles southeast of Prestonsburg on the Levisa Fork at the mouth of Beaver Creek. The area was settled in the nineteenth century, with more growth coming with the Chesapeake and Ohio Railroad in 1904. Allen City, also called Old Allen, is on the west side of Levisa Fork. On the other side of the Levisa is unincorporated New Allen, also called East Allen. The name Allen probably comes from a local storekeeper. The community was originally known as Beaver Creek and the railroad station was originally known as Beaver Creek Junction. Allen was incorporated in 1913. The first post office in the area was Mouth of Beaver, operating from 1854 to 1856. A later post office was called Catalpa Grove. The Allen post office opened in 1905. The Allen population was 193 in 2010. The population of New Allen is about 500.