Fennimore (town), Wisconsin. Fennimore is a town in Grant County, Wisconsin, United States. The population was 599 at the 2000 census. ... The unincorporated community of Preston is also located partially in the town. I thought this was neat to film, because how many small towns do you see with this kind of setting. Enjoy. Subscribe to my channel to be able to see all my stuff on places to see in Wisconsin. Thanks for watching.