One of Connecticut’s few examples of an Octagon house (which was popularized by Orson Squire Fowler in the 1850s) is in the Yalesville section of Wallingford. The house, located at 31 New Place Street (and one of two on the street) was built around 1856. (Edits to this entry are in bold).
31 New Place Street, Wallingford (1856)
There are actually two octagon houses on this street and your website seems to confuse them as being one house. The white house has an addition built in the back, the tan house does not. Also, for the back yard picture of the tan house, the image appears to be a inverted left to right. I only noticed this because I’ve lived in both houses. I believe the tan house was significantly renovated about ten years ago.
Thanks, I’ve just edited the post to fix the confusion!