Join Rich from Roam Around Tours on a Walking Tour of the Columbus Circle Historic District in Janesville. The Columbus Circle Historic District is a charming and compact neighborhood of modest sized homes in various styles popular between the 1920s to the 1940s. This was an era that home designs changed many revival styles that referenced past eras of history became popular. The architecture of Columbus Circle is a mix of old world and new with fairytale inspired looks, revival styles, and even post WWII modern styles.