1 definition found casselton - U.S. Gazetteer (1990) : Casselton, ND (city, FIPS 12700) Location: 46.90065 N, 97.21187 W Population (1990): 1601 (664 housing units) Area: 2.9 sq km (land), 0.1 sq km (water) Zip code(s): 58012