Bristol is a city located in western Day County, South Dakota, United States. Similar to many towns of the area and of the Midwest in geneā¦Bristol is a city located in western Day County, South Dakota, United States. Similar to many towns of the area and of the Midwest in general, Bristol came into being as a result of railroad expansion. The railroad, which first came through the area in the 1870s, identified the site which would become Bristol as Station #70. C.P. Prior, a district railroad surveyor and townsite agent, was given credit for naming Bristol in 1881. He named the town after Bristol, England.